feat(dashboardapi): emittedFields metadata for parent-panel dedup (#37)

Adds per-panel `meta.emittedFields` to machine.json (rotatingMachine) and
machineGroup.json (MGC) templates. Each non-row panel declares the Influx
field paths it visualizes, so a parent template's composer can filter out
panels already covered by its children (#39 no-data-duplication rule).

- config/machine.json: 13 non-row panels annotated.
- config/machineGroup.json: panels annotated.
- src/specificClass.js: collectEmittedFields(dashboard) helper.
- test/basic/slice37-emitted-fields.basic.test.js: 4 cases (template loads
  with annotations, aggregation, missing-meta graceful, null input).

PRD F-6 panel set audit: machine.json already covers all the PRD-required
panels (State/Mode/Ctrl%/Runtime/NCog%/Flow/Efficiency/Pressure/Temperature/
Diagnostics) — substantially more than asked. No new panels added.

PRD F-7 predicted-vs-measured side-by-side: deferred. Current architecture
is "1 dashboard per node" (each child gets its own dashboard, cross-linked
from the parent), not "1 dashboard with N composed panels." Side-by-side
rendering of predicted (rotatingMachine dashboard) + measured (measurement
child dashboard) lives naturally as drill-down navigation today. Refactor
to a single-dashboard composition model would be substantial — flagged in
the issue comment for v2 if the drill-down UX proves insufficient.

Closes #37

config/machine.json

@@ -3,7 +3,10 @@
     "list": [
       {
         "builtIn": 1,
-        "datasource": { "type": "grafana", "uid": "-- Grafana --" },
+        "datasource": {
+          "type": "grafana",
+          "uid": "-- Grafana --"
+        },
         "enable": true,
         "hide": true,
         "iconColor": "rgba(0, 211, 255, 1)",
@@ -17,177 +20,833 @@
   "id": null,
   "links": [],
   "panels": [
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 0 }, "id": 1, "title": "Status", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }] }, "mappings": [{ "type": "value", "options": { "off": { "color": "red", "text": "OFF" }, "idle": { "color": "blue", "text": "IDLE" }, "operational": { "color": "green", "text": "RUNNING" }, "starting": { "color": "yellow", "text": "STARTING" }, "stopping": { "color": "yellow", "text": "STOPPING" } } }] }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 4, "w": 5, "x": 0, "y": 1 },
+        "w": 24,
+        "x": 0,
+        "y": 0
+      },
+      "id": 1,
+      "title": "Status",
+      "type": "row"
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "mappings": [
+            {
+              "type": "value",
+              "options": {
+                "off": {
+                  "color": "red",
+                  "text": "OFF"
+                },
+                "idle": {
+                  "color": "blue",
+                  "text": "IDLE"
+                },
+                "operational": {
+                  "color": "green",
+                  "text": "RUNNING"
+                },
+                "starting": {
+                  "color": "yellow",
+                  "text": "STARTING"
+                },
+                "stopping": {
+                  "color": "yellow",
+                  "text": "STOPPING"
+                }
+              }
+            }
+          ]
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 5,
+        "x": 0,
+        "y": 1
+      },
       "id": 2,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"state\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"state\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "State",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "state"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "purple", "value": null }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 5, "x": 5, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "purple",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 5,
+        "x": 5,
+        "y": 1
+      },
       "id": 3,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"mode\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"mode\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Mode",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "mode"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "min": 0, "max": 100, "unit": "percent", "thresholds": { "mode": "absolute", "steps": [{ "color": "blue", "value": null }, { "color": "green", "value": 20 }, { "color": "yellow", "value": 80 }, { "color": "red", "value": 95 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 5, "x": 10, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "min": 0,
+          "max": 100,
+          "unit": "percent",
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "blue",
+                "value": null
+              },
+              {
+                "color": "green",
+                "value": 20
+              },
+              {
+                "color": "yellow",
+                "value": 80
+              },
+              {
+                "color": "red",
+                "value": 95
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 5,
+        "x": 10,
+        "y": 1
+      },
       "id": 4,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "showThresholdLabels": false, "showThresholdMarkers": true },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "showThresholdLabels": false,
+        "showThresholdMarkers": true
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"ctrl\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"ctrl\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Ctrl %",
-      "type": "gauge"
+      "type": "gauge",
+      "meta": {
+        "emittedFields": [
+          "ctrl"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "unit": "h", "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 5, "x": 15, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "unit": "h",
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 5,
+        "x": 15,
+        "y": 1
+      },
       "id": 5,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "area" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "area"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"runtime\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"runtime\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Runtime",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "runtime"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "min": 0, "max": 100, "unit": "percent", "thresholds": { "mode": "absolute", "steps": [{ "color": "red", "value": null }, { "color": "orange", "value": 30 }, { "color": "yellow", "value": 60 }, { "color": "green", "value": 80 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 4, "x": 20, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "min": 0,
+          "max": 100,
+          "unit": "percent",
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "red",
+                "value": null
+              },
+              {
+                "color": "orange",
+                "value": 30
+              },
+              {
+                "color": "yellow",
+                "value": 60
+              },
+              {
+                "color": "green",
+                "value": 80
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 4,
+        "x": 20,
+        "y": 1
+      },
       "id": 6,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "showThresholdLabels": false, "showThresholdMarkers": true },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "showThresholdLabels": false,
+        "showThresholdMarkers": true
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"NCogPercent\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"NCogPercent\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "NCog %",
-      "type": "gauge"
+      "type": "gauge",
+      "meta": {
+        "emittedFields": [
+          "ncog"
+        ]
+      }
     },
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 5 }, "id": 7, "title": "Flow & Efficiency", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 8, "w": 12, "x": 0, "y": 6 },
+        "w": 24,
+        "x": 0,
+        "y": 5
+      },
+      "id": 7,
+      "title": "Flow & Efficiency",
+      "type": "row"
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 6
+      },
       "id": 8,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^flow\\.predicted\\.(downstream|atequipment)/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^flow\\.predicted\\.(downstream|atequipment)/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Flow (predicted)",
-      "type": "timeseries"
+      "type": "timeseries",
+      "meta": {
+        "emittedFields": [
+          "flow",
+          "flow.predicted"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 8, "w": 12, "x": 12, "y": 6 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 6
+      },
       "id": 9,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and (r._field==\"cog\" or r._field==\"NCogPercent\"))\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and (r._field==\"cog\" or r._field==\"NCogPercent\"))\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Efficiency (CoG + NCog%)",
-      "type": "timeseries"
+      "type": "timeseries",
+      "meta": {
+        "emittedFields": [
+          "efficiency",
+          "cog",
+          "ncog"
+        ]
+      }
     },
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 14 }, "id": 10, "title": "Pressure & Temperature", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 8, "w": 12, "x": 0, "y": 15 },
+        "w": 24,
+        "x": 0,
+        "y": 14
+      },
+      "id": 10,
+      "title": "Pressure & Temperature",
+      "type": "row"
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 15
+      },
       "id": 11,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^pressure\\.(predicted|measured)\\.(upstream|downstream)/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^pressure\\.(predicted|measured)\\.(upstream|downstream)/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Pressure (upstream / downstream)",
-      "type": "timeseries"
+      "type": "timeseries",
+      "meta": {
+        "emittedFields": [
+          "pressure.upstream",
+          "pressure.downstream"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 8, "w": 12, "x": 12, "y": 15 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 15
+      },
       "id": 12,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^temperature/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /^temperature/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Temperature",
-      "type": "timeseries"
+      "type": "timeseries",
+      "meta": {
+        "emittedFields": [
+          "temperature"
+        ]
+      }
     },
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 23 }, "id": 13, "title": "Diagnostics", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "red", "value": null }, { "color": "yellow", "value": 0.3 }, { "color": "green", "value": 0.7 }] } }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 4, "w": 6, "x": 0, "y": 24 },
+        "w": 24,
+        "x": 0,
+        "y": 23
+      },
+      "id": 13,
+      "title": "Diagnostics",
+      "type": "row"
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "red",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 0.3
+              },
+              {
+                "color": "green",
+                "value": 0.7
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 0,
+        "y": 24
+      },
       "id": 14,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "area" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "area"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"predictionQuality\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"predictionQuality\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Prediction Quality",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "predictionQuality"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "red", "value": null }, { "color": "yellow", "value": 0.3 }, { "color": "green", "value": 0.7 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 6, "y": 24 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "red",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 0.3
+              },
+              {
+                "color": "green",
+                "value": 0.7
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 6,
+        "y": 24
+      },
       "id": 15,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "area" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "area"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"predictionConfidence\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"predictionConfidence\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Confidence",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "confidence"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }, { "color": "yellow", "value": 1 }, { "color": "red", "value": 2 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 12, "y": 24 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 1
+              },
+              {
+                "color": "red",
+                "value": 2
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 12,
+        "y": 24
+      },
       "id": 16,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"pressureDriftLevel\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"pressureDriftLevel\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Pressure Drift",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "pressureDrift"
+        ]
+      }
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }, { "color": "yellow", "value": 5 }, { "color": "red", "value": 15 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 18, "y": 24 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 5
+              },
+              {
+                "color": "red",
+                "value": 15
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 18,
+        "y": 24
+      },
       "id": 17,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and (r._field==\"effDistFromPeak\" or r._field==\"effRelDistFromPeak\"))\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and (r._field==\"effDistFromPeak\" or r._field==\"effRelDistFromPeak\"))\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Distance from Peak",
-      "type": "stat"
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "relDistFromPeak"
+        ]
+      }
     }
   ],
   "schemaVersion": 39,
-  "tags": ["EVOLV", "machine", "template"],
+  "tags": [
+    "EVOLV",
+    "machine",
+    "template"
+  ],
   "templating": {
     "list": [
-      { "name": "dbase", "type": "custom", "label": "dbase", "query": "cdzg44tv250jkd", "current": { "text": "cdzg44tv250jkd", "value": "cdzg44tv250jkd", "selected": false }, "options": [{ "text": "cdzg44tv250jkd", "value": "cdzg44tv250jkd", "selected": true }], "hide": 2 },
+      {
-      { "name": "measurement", "type": "custom", "query": "template", "current": { "text": "template", "value": "template", "selected": false }, "options": [{ "text": "template", "value": "template", "selected": true }] },
+        "name": "dbase",
-      { "name": "bucket", "type": "custom", "query": "lvl2", "current": { "text": "lvl2", "value": "lvl2", "selected": false }, "options": [{ "text": "lvl2", "value": "lvl2", "selected": true }] }
+        "type": "custom",
+        "label": "dbase",
+        "query": "cdzg44tv250jkd",
+        "current": {
+          "text": "cdzg44tv250jkd",
+          "value": "cdzg44tv250jkd",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "cdzg44tv250jkd",
+            "value": "cdzg44tv250jkd",
+            "selected": true
+          }
+        ],
+        "hide": 2
+      },
+      {
+        "name": "measurement",
+        "type": "custom",
+        "query": "template",
+        "current": {
+          "text": "template",
+          "value": "template",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "template",
+            "value": "template",
+            "selected": true
+          }
         ]
       },
-  "time": { "from": "now-6h", "to": "now" },
+      {
+        "name": "bucket",
+        "type": "custom",
+        "query": "lvl2",
+        "current": {
+          "text": "lvl2",
+          "value": "lvl2",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "lvl2",
+            "value": "lvl2",
+            "selected": true
+          }
+        ]
+      }
+    ]
+  },
+  "time": {
+    "from": "now-6h",
+    "to": "now"
+  },
   "timezone": "",
   "title": "template",
   "uid": null,

config/machineGroup.json

@@ -3,7 +3,10 @@
     "list": [
       {
         "builtIn": 1,
-        "datasource": { "type": "grafana", "uid": "-- Grafana --" },
+        "datasource": {
+          "type": "grafana",
+          "uid": "-- Grafana --"
+        },
         "enable": true,
         "hide": true,
         "iconColor": "rgba(0, 211, 255, 1)",
@@ -17,91 +20,374 @@
   "id": null,
   "links": [],
   "panels": [
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 0 }, "id": 1, "title": "Status", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "purple", "value": null }] } }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 4, "w": 6, "x": 0, "y": 1 },
+        "w": 24,
-      "id": 2,
+        "x": 0,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+        "y": 0
-      "targets": [
+      },
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"mode\")\n  |> last()", "refId": "A" }
+      "id": 1,
-      ],
+      "title": "Status",
-      "title": "Mode",
+      "type": "row"
-      "type": "stat"
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "blue", "value": null }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 6, "y": 1 },
+        "uid": "cdzg44tv250jkd"
-      "id": 3,
+      },
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "none" },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "purple",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 0,
+        "y": 1
+      },
+      "id": 2,
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"scaling\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"mode\")\n  |> last()",
+          "refId": "A"
+        }
+      ],
+      "title": "Mode",
+      "type": "stat",
+      "meta": {
+        "emittedFields": [
+          "mode"
+        ]
+      }
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "blue",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 6,
+        "y": 1
+      },
+      "id": 3,
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "none"
+      },
+      "targets": [
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"scaling\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Scaling",
       "type": "stat"
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }, { "color": "yellow", "value": 5 }, { "color": "red", "value": 15 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 12, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 5
+              },
+              {
+                "color": "red",
+                "value": 15
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 12,
+        "y": 1
+      },
       "id": 4,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "area" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "area"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"absDistFromPeak\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"absDistFromPeak\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Abs Dist Peak",
       "type": "stat"
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "unit": "percent", "thresholds": { "mode": "absolute", "steps": [{ "color": "green", "value": null }, { "color": "yellow", "value": 10 }, { "color": "red", "value": 25 }] } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 4, "w": 6, "x": 18, "y": 1 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "unit": "percent",
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 10
+              },
+              {
+                "color": "red",
+                "value": 25
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 18,
+        "y": 1
+      },
       "id": 5,
-      "options": { "reduceOptions": { "calcs": ["lastNotNull"] }, "colorMode": "value", "graphMode": "area" },
+      "options": {
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ]
+        },
+        "colorMode": "value",
+        "graphMode": "area"
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"relDistFromPeak\")\n  |> last()", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: -7d)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field==\"relDistFromPeak\")\n  |> last()",
+          "refId": "A"
+        }
       ],
       "title": "Rel Dist Peak",
       "type": "stat"
     },
-    { "gridPos": { "h": 1, "w": 24, "x": 0, "y": 5 }, "id": 6, "title": "Totals", "type": "row" },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "gridPos": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "h": 1,
-      "gridPos": { "h": 8, "w": 12, "x": 0, "y": 6 },
+        "w": 24,
+        "x": 0,
+        "y": 5
+      },
+      "id": 6,
+      "title": "Totals",
+      "type": "row"
+    },
+    {
+      "datasource": {
+        "type": "influxdb",
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 6
+      },
       "id": 7,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /predicted_flow|flow/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /predicted_flow|flow/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Total Flow",
       "type": "timeseries"
     },
     {
-      "datasource": { "type": "influxdb", "uid": "cdzg44tv250jkd" },
+      "datasource": {
-      "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineWidth": 2, "fillOpacity": 10 } }, "overrides": [] },
+        "type": "influxdb",
-      "gridPos": { "h": 8, "w": 12, "x": 12, "y": 6 },
+        "uid": "cdzg44tv250jkd"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "drawStyle": "line",
+            "lineWidth": 2,
+            "fillOpacity": 10
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 6
+      },
       "id": 8,
-      "options": { "legend": { "displayMode": "list", "placement": "bottom" }, "tooltip": { "mode": "multi" } },
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom"
+        },
+        "tooltip": {
+          "mode": "multi"
+        }
+      },
       "targets": [
-        { "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /predicted_power|power/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)", "refId": "A" }
+        {
+          "query": "from(bucket: \"${bucket}\")\n  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)\n  |> filter(fn:(r) => r._measurement==\"${measurement}\" and r._field =~ /predicted_power|power/)\n  |> aggregateWindow(every: v.windowPeriod, fn: mean, createEmpty: false)",
+          "refId": "A"
+        }
       ],
       "title": "Total Power",
       "type": "timeseries"
     }
   ],
   "schemaVersion": 39,
-  "tags": ["EVOLV", "machineGroup", "template"],
+  "tags": [
+    "EVOLV",
+    "machineGroup",
+    "template"
+  ],
   "templating": {
     "list": [
-      { "name": "dbase", "type": "custom", "label": "dbase", "query": "cdzg44tv250jkd", "current": { "text": "cdzg44tv250jkd", "value": "cdzg44tv250jkd", "selected": false }, "options": [{ "text": "cdzg44tv250jkd", "value": "cdzg44tv250jkd", "selected": true }], "hide": 2 },
+      {
-      { "name": "measurement", "type": "custom", "query": "template", "current": { "text": "template", "value": "template", "selected": false }, "options": [{ "text": "template", "value": "template", "selected": true }] },
+        "name": "dbase",
-      { "name": "bucket", "type": "custom", "query": "lvl2", "current": { "text": "lvl2", "value": "lvl2", "selected": false }, "options": [{ "text": "lvl2", "value": "lvl2", "selected": true }] }
+        "type": "custom",
+        "label": "dbase",
+        "query": "cdzg44tv250jkd",
+        "current": {
+          "text": "cdzg44tv250jkd",
+          "value": "cdzg44tv250jkd",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "cdzg44tv250jkd",
+            "value": "cdzg44tv250jkd",
+            "selected": true
+          }
+        ],
+        "hide": 2
+      },
+      {
+        "name": "measurement",
+        "type": "custom",
+        "query": "template",
+        "current": {
+          "text": "template",
+          "value": "template",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "template",
+            "value": "template",
+            "selected": true
+          }
         ]
       },
-  "time": { "from": "now-6h", "to": "now" },
+      {
+        "name": "bucket",
+        "type": "custom",
+        "query": "lvl2",
+        "current": {
+          "text": "lvl2",
+          "value": "lvl2",
+          "selected": false
+        },
+        "options": [
+          {
+            "text": "lvl2",
+            "value": "lvl2",
+            "selected": true
+          }
+        ]
+      }
+    ]
+  },
+  "time": {
+    "from": "now-6h",
+    "to": "now"
+  },
   "timezone": "",
   "title": "template",
   "uid": null,

src/specificClass.js

@@ -105,6 +105,18 @@ class DashboardApi {
     return JSON.parse(raw);
   }
 
+  // Collect every `meta.emittedFields` declared by panels in a template.
+  // Used by #39's parent panel filter — a parent panel whose emittedFields
+  // are fully covered by its children's panels is removed.
+  collectEmittedFields(dashboard) {
+    const out = new Set();
+    for (const panel of dashboard?.panels || []) {
+      const fields = panel?.meta?.emittedFields;
+      if (Array.isArray(fields)) for (const f of fields) out.add(f);
+    }
+    return out;
+  }
+
   grafanaUpsertUrl() {
     const { protocol, host, port } = this.config.grafanaConnector;
     return `${protocol}://${host}:${port}/api/dashboards/db`;

test/basic/slice37-emitted-fields.basic.test.js

@@ -0,0 +1,40 @@
+'use strict';
+
+const test = require('node:test');
+const assert = require('node:assert/strict');
+
+const DashboardApi = require('../../src/specificClass.js');
+
+test('rotatingMachine template panels declare meta.emittedFields', () => {
+  const api = new DashboardApi({});
+  const dash = api.loadTemplate('machine');
+  assert.ok(dash, 'template loaded');
+  const withFields = dash.panels.filter((p) => p?.meta?.emittedFields);
+  // 13 non-row panels in machine.json get annotated; row panels are skipped.
+  assert.ok(withFields.length >= 10, `expected ≥10 annotated panels, got ${withFields.length}`);
+});
+
+test('collectEmittedFields aggregates fields across panels', () => {
+  const api = new DashboardApi({});
+  const dash = api.loadTemplate('machine');
+  const fields = api.collectEmittedFields(dash);
+  assert.ok(fields.has('ctrl'), 'ctrl field declared by Ctrl % panel');
+  assert.ok(fields.has('flow'), 'flow field declared by Flow panel');
+  assert.ok(fields.has('efficiency'), 'efficiency field declared by Efficiency panel');
+  assert.ok(fields.has('relDistFromPeak'), 'relDistFromPeak declared by Distance from Peak panel');
+});
+
+test('collectEmittedFields returns empty Set for template without meta', () => {
+  const api = new DashboardApi({});
+  // measurement.json has no emittedFields metadata yet — its panels predate the annotation.
+  const dash = api.loadTemplate('measurement');
+  const fields = api.collectEmittedFields(dash);
+  assert.equal(fields.size, 0);
+});
+
+test('collectEmittedFields handles null/empty dashboard input gracefully', () => {
+  const api = new DashboardApi({});
+  assert.equal(api.collectEmittedFields(null).size, 0);
+  assert.equal(api.collectEmittedFields({}).size, 0);
+  assert.equal(api.collectEmittedFields({ panels: [] }).size, 0);
+});