chore(dashboardAPI): bigger rim/floor labels with guaranteed clearance

Rim ('rim (X m)') and floor ('floor (0.00 m)') captions now use the same
size 14 font as the threshold labels (was size 10 — visibly smaller and
hard to read on a high-resolution dashboard). To make room for the larger
text while ensuring rim/floor can NEVER overlap the topmost (overflow) or
bottommost (outflow) threshold lines at any basin geometry, the tank's
vertical margins are bumped from 40 px to 48 px each:

  TANK_TOP: 40 -> 48,  TANK_BOT: 720 -> 712,  TANK_H: 680 -> 664

Rim placement: top:1, bottom:95 (4 % tall band at the top, spanning 7.6 -> 38 px).
Floor placement: top:95, bottom:1 (4 % tall band at the bottom).
The topmost threshold line (overflow at max basinHeight) sits at TANK_TOP=48 px,
leaving 10 px clearance above the line. Same for the bottommost (outflow) line.

Color: #8a8a8a -> #6a6a6a (slightly darker so it reads at the bigger size).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

config/pumpingStation.json

@@ -235,7 +235,7 @@
               "name": "Zone Spill",
               "type": "rectangle",
               "constraint": { "horizontal": "scale", "vertical": "scale" },
-              "placement": { "top": 5.26, "left": 2.5, "right": 2.5, "bottom": {{zb_spill}} },
+              "placement": { "top": 6.32, "left": 2.5, "right": 2.5, "bottom": {{zb_spill}} },
               "background": { "color": { "fixed": "rgba(229, 67, 67, 0.18)" } },
               "border": { "color": { "fixed": "transparent" }, "width": 0 },
               "config": { "text": { "mode": "fixed", "fixed": "" } }
@@ -271,7 +271,7 @@
               "name": "Tank Outline",
               "type": "rectangle",
               "constraint": { "horizontal": "scale", "vertical": "scale" },
-              "placement": { "top": 5.26, "left": 2.5, "right": 2.5, "bottom": 5.27 },
+              "placement": { "top": 6.32, "left": 2.5, "right": 2.5, "bottom": 6.32 },
               "background": { "color": { "fixed": "transparent" } },
               "border": { "color": { "fixed": "#8a8a8a" }, "width": 2 },
               "config": { "text": { "mode": "fixed", "fixed": "" } }
@@ -410,19 +410,19 @@
               "name": "Header Rim",
               "type": "text",
               "constraint": { "horizontal": "scale", "vertical": "scale" },
-              "placement": { "top": 2.63, "left": 2.5, "right": 2.5, "bottom": 95.26 },
+              "placement": { "top": 1, "left": 2.5, "right": 2.5, "bottom": 95 },
               "background": { "color": { "fixed": "transparent" } },
               "border": { "color": { "fixed": "transparent" }, "width": 0 },
-              "config": { "text": { "mode": "fixed", "fixed": "rim ({{heightBasin}} m)" }, "color": { "fixed": "#8a8a8a" }, "size": 10, "align": "center", "valign": "middle" }
+              "config": { "text": { "mode": "fixed", "fixed": "rim ({{heightBasin}} m)" }, "color": { "fixed": "#6a6a6a" }, "size": 14, "align": "center", "valign": "middle" }
             },
             {
               "name": "Footer Floor",
               "type": "text",
               "constraint": { "horizontal": "scale", "vertical": "scale" },
-              "placement": { "top": 95.26, "left": 2.5, "right": 2.5, "bottom": 2.63 },
+              "placement": { "top": 95, "left": 2.5, "right": 2.5, "bottom": 1 },
               "background": { "color": { "fixed": "transparent" } },
               "border": { "color": { "fixed": "transparent" }, "width": 0 },
-              "config": { "text": { "mode": "fixed", "fixed": "floor (0.00 m)" }, "color": { "fixed": "#8a8a8a" }, "size": 10, "align": "center", "valign": "middle" }
+              "config": { "text": { "mode": "fixed", "fixed": "floor (0.00 m)" }, "color": { "fixed": "#6a6a6a" }, "size": 14, "align": "center", "valign": "middle" }
             }
           ]
         }

src/specificClass.js

@@ -194,10 +194,13 @@ class DashboardApi {
     // Grafana interprets placement values as PERCENTAGES of the panel size,
     // not pixels — so the basin stretches to fill the card at any viewport
     // and stays centered without letterboxing.
-    // Tank reference: rim at y=40px (5.26%), floor at y=720px (94.74%),
+    // Tank reference: rim at y=48px (6.32%), floor at y=712px (93.68%),
-    // centred vertically with 40px top/bottom margins for rim/floor labels.
+    // centred vertically with 48px top/bottom margins. Margins are sized
+    // so the size-14 'rim (X m)' and 'floor (0.00 m)' captions fit with
+    // ~10 px clearance from the topmost/bottommost threshold line — labels
+    // can never collide with a line at any basin geometry.
     const FRAME_W = 400, FRAME_H = 760;
-    const TANK_TOP = 40, TANK_BOT = 720, TANK_H = TANK_BOT - TANK_TOP;
+    const TANK_TOP = 48, TANK_BOT = 712, TANK_H = TANK_BOT - TANK_TOP;
     const yp = (v) => +(v / FRAME_H * 100).toFixed(2);
     const xp = (v) => +(v / FRAME_W * 100).toFixed(2);
     const hp = (v) => +(v / FRAME_H * 100).toFixed(2);