example(dashboardapi): basic.flow.json demos end-to-end Grafana round-trip (#42)

Replaces the placeholder inject→dashboardapi→debug example with the full
chain: inject (simulating a measurement child registration) → dashboardapi
(composes dashboard JSON) → http request (POSTs to Grafana) → debug (shows
the response). Default targets http://grafana:3000 inside the Docker compose
network. Configure bearer token via the encrypted credentials field.

Refs #42

examples/basic.flow.json

@@ -1,6 +1,70 @@
 [
-  {"id":"dashboardAPI_basic_tab","type":"tab","label":"dashboardAPI basic","disabled":false,"info":"dashboardAPI basic example"},
-  {"id":"dashboardAPI_basic_node","type":"dashboardapi","z":"dashboardAPI_basic_tab","name":"dashboardAPI basic","x":420,"y":180,"wires":[["dashboardAPI_basic_dbg"]]},
-  {"id":"dashboardAPI_basic_inj","type":"inject","z":"dashboardAPI_basic_tab","name":"basic trigger","props":[{"p":"topic","vt":"str"},{"p":"payload","vt":"str"}],"topic":"ping","payload":"1","payloadType":"str","x":160,"y":180,"wires":[["dashboardAPI_basic_node"]]},
-  {"id":"dashboardAPI_basic_dbg","type":"debug","z":"dashboardAPI_basic_tab","name":"dashboardAPI basic debug","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","x":660,"y":180,"wires":[]}
+  {
+    "id": "dashboardAPI_basic_tab",
+    "type": "tab",
+    "label": "dashboardAPI basic — measurement → Grafana",
+    "disabled": false,
+    "info": "Demonstrates the round-trip:\n- inject simulates a child.register message from a measurement node\n- dashboardapi composes a Grafana dashboard for that child\n- http request posts the dashboard to Grafana\n- debug shows the HTTP response\n\nConfigure the dashboardapi node with your Grafana host/port + bearer token\n(encrypted via Node-RED credentials). Default targets http://grafana:3000\nfrom inside the Docker compose stack."
+  },
+  {
+    "id": "dashboardAPI_basic_node",
+    "type": "dashboardapi",
+    "z": "dashboardAPI_basic_tab",
+    "name": "dashboardAPI",
+    "protocol": "http",
+    "host": "grafana",
+    "port": 3000,
+    "folderUid": "",
+    "defaultBucket": "telemetry",
+    "x": 460,
+    "y": 200,
+    "wires": [["dashboardAPI_basic_http"]]
+  },
+  {
+    "id": "dashboardAPI_basic_inj",
+    "type": "inject",
+    "z": "dashboardAPI_basic_tab",
+    "name": "simulate child.register (measurement)",
+    "props": [
+      { "p": "topic", "vt": "str" },
+      { "p": "payload", "v": "{\"config\":{\"general\":{\"id\":\"meas-demo-001\",\"name\":\"FT-001 demo\"},\"functionality\":{\"softwareType\":\"measurement\",\"positionVsParent\":\"downstream\"}}}", "vt": "json" }
+    ],
+    "topic": "child.register",
+    "x": 180,
+    "y": 200,
+    "wires": [["dashboardAPI_basic_node"]]
+  },
+  {
+    "id": "dashboardAPI_basic_http",
+    "type": "http request",
+    "z": "dashboardAPI_basic_tab",
+    "name": "POST /api/dashboards/db",
+    "method": "use",
+    "ret": "obj",
+    "paytoqs": "ignore",
+    "url": "",
+    "tls": "",
+    "persist": false,
+    "proxy": "",
+    "authType": "",
+    "senderr": false,
+    "x": 720,
+    "y": 200,
+    "wires": [["dashboardAPI_basic_dbg"]]
+  },
+  {
+    "id": "dashboardAPI_basic_dbg",
+    "type": "debug",
+    "z": "dashboardAPI_basic_tab",
+    "name": "Grafana response",
+    "active": true,
+    "tosidebar": true,
+    "console": false,
+    "tostatus": false,
+    "complete": "payload",
+    "targetType": "msg",
+    "x": 960,
+    "y": 200,
+    "wires": []
+  }
 ]