Editor: nudge crowded threshold inputs off their lines with leader lines

When real wastewater values cluster near the basin floor (minLevel,
dryRunLevel, outflowLevel are often within a few cm of each other),
the threshold inputs were stacking on top of each other. Now:

- Threshold LINE stays at its proportional y on the tank (visual
  truth: that's where the level actually is).
- Input BOX / label / unit are positioned in a nudged right-column
  stack with a minimum 26-px gap so they never overlap.
- A dashed grey leader line connects each line to its input when
  they had to be pulled apart, so the association stays visible.
- Items are sorted by ideal y top-down and nudged downward once;
  basinHeight is pinned at the rim and acts as the anchor.

Also: viewBox extended 430 → 480 so the bottom-of-stack items have
room below the tank when the bottom cluster is tight. Warning ribbon
moved to y=460 accordingly.

No schema change; purely UI layout.

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

pumpingStation.html

@@ -188,52 +188,113 @@
         const y = DIAG.botY - (val / basinH) * (DIAG.botY - DIAG.topY);
         return Math.max(DIAG.topY - 8, Math.min(DIAG.botY + 8, y));
       };
-      const placeRow = (id, y) => {
-        if (y == null) return;
-        const line = document.getElementById(`ps-line-${id}`);
+      // Place a right-column item. yLine is the threshold's true
+      // proportional position on the tank; yInput is where the label
+      // and input box land (may be nudged away from yLine to avoid
+      // overlap with neighbouring items). A dashed leader line is
+      // shown only when the two differ by more than a pixel or two.
+      const placeItem = (id, yLine, yInput) => {
+        const line  = document.getElementById(`ps-line-${id}`);
         const label = document.getElementById(`ps-label-${id}`);
-        const unit = document.getElementById(`ps-unit-${id}`);
-        const fo = document.getElementById(`ps-fo-${id}`);
-        const sub = document.getElementById(`ps-sub-${id}`);
-        if (line) { line.setAttribute('y1', y); line.setAttribute('y2', y); }
-        if (label) label.setAttribute('y', y + 4);
-        if (unit) unit.setAttribute('y', y + 4);
-        if (fo) fo.setAttribute('y', y - 11);
-        if (sub) sub.setAttribute('y', y + 15);
+        const unit  = document.getElementById(`ps-unit-${id}`);
+        const fo    = document.getElementById(`ps-fo-${id}`);
+        const sub   = document.getElementById(`ps-sub-${id}`);
+        const lead  = document.getElementById(`ps-leader-${id}`);
+        if (line)  { line.setAttribute('y1', yLine); line.setAttribute('y2', yLine); }
+        if (label) label.setAttribute('y', yInput + 4);
+        if (unit)  unit.setAttribute('y', yInput + 4);
+        if (fo)    fo.setAttribute('y', yInput - 11);
+        if (sub)   sub.setAttribute('y', yInput + 15);
+        if (lead) {
+          if (Math.abs(yLine - yInput) > 2) {
+            lead.setAttribute('x1', 325); lead.setAttribute('y1', yLine);
+            lead.setAttribute('x2', 420); lead.setAttribute('y2', yInput);
+            lead.setAttribute('visibility', 'visible');
+          } else {
+            lead.setAttribute('visibility', 'hidden');
+          }
+        }
       };
+
       const redraw = () => {
         const basinH = fNum('basinHeight') || 5;
-        placeRow('overflowLevel', yForLevel(fNum('overflowLevel'), basinH));
-        placeRow('maxLevel',      yForLevel(fNum('maxLevel'),      basinH));
-        placeRow('startLevel',    yForLevel(fNum('startLevel'),    basinH));
-        placeRow('minLevel',      yForLevel(fNum('minLevel'),      basinH));
-        placeRow('inflowLevel',   yForLevel(fNum('inflowLevel'),   basinH));
+
+        // Derived safety levels (participate in the right-column stack)
+        const basedOn = document.getElementById('node-input-minHeightBasedOn')?.value || 'outlet';
+        const refLow  = basedOn === 'inlet' ? fNum('inflowLevel') : fNum('outflowLevel');
+        const dryPct  = fNum('dryRunThresholdPercent');
+        const ovfPct  = fNum('overfillThresholdPercent');
+        const ovf     = fNum('overflowLevel');
+        const dryLvl  = (refLow != null && dryPct != null) ? refLow * (1 + dryPct / 100) : null;
+        const ovfLvl  = (ovf    != null && ovfPct != null) ? ovf    * (ovfPct / 100)     : null;
+
+        // Build the right-column items. basinHeight is pinned at the
+        // rim (DIAG.topY); others float on the proportional axis and
+        // get nudged apart so the input boxes don't overlap.
+        const items = [
+          { id: 'basinHeight',   yLine: DIAG.topY, pinned: true },
+          { id: 'overflowLevel', yLine: yForLevel(fNum('overflowLevel'), basinH) },
+          { id: 'maxLevel',      yLine: yForLevel(fNum('maxLevel'),      basinH) },
+          { id: 'startLevel',    yLine: yForLevel(fNum('startLevel'),    basinH) },
+          { id: 'minLevel',      yLine: yForLevel(fNum('minLevel'),      basinH) },
+          { id: 'dryRunLevel',   yLine: yForLevel(dryLvl,                basinH) },
+          { id: 'outflowLevel',  yLine: yForLevel(fNum('outflowLevel'),  basinH) },
+        ].filter(it => it.yLine != null);
+
+        const GAP = 26;
+        items.sort((a, b) => a.yLine - b.yLine);
+        let prev = -Infinity;
+        for (const it of items) {
+          if (it.pinned) { it.yInput = it.yLine; prev = it.yInput; continue; }
+          it.yInput = Math.max(it.yLine, prev + GAP);
+          prev = it.yInput;
+        }
+
+        // Hide leader lines for items whose input is cleared
+        const active = new Set(items.map(it => it.id));
+        ['overflowLevel','maxLevel','startLevel','minLevel','dryRunLevel','outflowLevel'].forEach(id => {
+          if (!active.has(id)) {
+            const lead = document.getElementById(`ps-leader-${id}`);
+            if (lead) lead.setAttribute('visibility', 'hidden');
+          }
+        });
+        for (const it of items) placeItem(it.id, it.yLine, it.yInput);
+
+        // Inlet arrow — sole item on the left, no stacking concerns
+        const inflowY = yForLevel(fNum('inflowLevel'), basinH);
+        if (inflowY != null) {
+          const line = document.getElementById('ps-line-inflowLevel');
+          const lbl  = document.getElementById('ps-label-inflowLevel');
+          const sub  = document.getElementById('ps-sub-inflowLevel');
+          const fo   = document.getElementById('ps-fo-inflowLevel');
+          const unit = document.getElementById('ps-unit-inflowLevel');
+          if (line) { line.setAttribute('y1', inflowY); line.setAttribute('y2', inflowY); }
+          if (lbl)  lbl.setAttribute('y', inflowY - 4);
+          if (sub)  sub.setAttribute('y', inflowY + 8);
+          if (fo)   fo.setAttribute('y', inflowY - 11);
+          if (unit) unit.setAttribute('y', inflowY + 4);
+        }
+
+        // Dead-volume band: from outflowLevel down to the floor
         const outflowY = yForLevel(fNum('outflowLevel'), basinH);
-        placeRow('outflowLevel', outflowY);
-        // Dead-volume band fills from outflowLevel down to the floor
-        const deadvol = document.getElementById('ps-deadvol');
+        const deadvol  = document.getElementById('ps-deadvol');
         if (deadvol && outflowY != null) {
           deadvol.setAttribute('y', outflowY);
           deadvol.setAttribute('height', Math.max(0, DIAG.botY - outflowY));
         }
-        // Derived dryRunLevel (safety, from %)
-        const basedOn = document.getElementById('node-input-minHeightBasedOn')?.value || 'outlet';
-        const refLow = basedOn === 'inlet' ? fNum('inflowLevel') : fNum('outflowLevel');
-        const dryPct = fNum('dryRunThresholdPercent');
-        const ovfPct = fNum('overfillThresholdPercent');
-        const ovf    = fNum('overflowLevel');
-        const dryLvl = (refLow != null && dryPct != null) ? refLow * (1 + dryPct / 100) : null;
-        const ovfLvl = (ovf    != null && ovfPct != null) ? ovf    * (ovfPct / 100)     : null;
-        placeRow('dryRunLevel', yForLevel(dryLvl, basinH));
+
+        // dryRunLevel label text (derived, read-only)
         const dryLbl = document.getElementById('ps-label-dryRunLevel');
         if (dryLbl) dryLbl.textContent = dryLvl != null
           ? `dryRunLevel ≈ ${dryLvl.toFixed(2)} m (safety — from %)`
           : 'dryRunLevel ≈ — m (safety — from %)';
-        // Safety-section readouts (same values, second view)
+
+        // Safety-section readouts (second view, beneath the diagram)
         const d1 = document.getElementById('derived-dryRunLevel');
         if (d1) d1.textContent = dryLvl != null ? `→ dryRunLevel ≈ ${dryLvl.toFixed(2)} m` : '→ dryRunLevel ≈ — m';
         const d2 = document.getElementById('derived-overfillLevel');
         if (d2) d2.textContent = ovfLvl != null ? `→ overfillLevel ≈ ${ovfLvl.toFixed(2)} m` : '→ overfillLevel ≈ — m';
+
         // Ordering warning ribbon
         const warn = document.getElementById('ps-warning');
         const issues = [];
@@ -324,7 +385,7 @@
     #ps-basin-diagram input[type=number]:focus { outline: 1px solid #0c99d9; border-color: #0c99d9; }
   </style>
 
-  <svg id="ps-basin-diagram" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 520 430"
+  <svg id="ps-basin-diagram" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 520 480"
        style="display:block;width:100%;max-width:540px;margin:0 0 12px 0;background:#fff;border:1px solid #e5e5e5;border-radius:4px;"
        font-family="Arial,sans-serif" font-size="11">
     <defs>
@@ -404,8 +465,17 @@
     <line x1="195" y1="380" x2="325" y2="380" stroke="#000" stroke-width="2" />
     <text x="330" y="384" fill="#000">0 m (datum)</text>
 
+    <!-- Leader lines: shown when the input row had to be nudged off its threshold's ideal y -->
+    <line id="ps-leader-basinHeight"   x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-overflowLevel" x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-maxLevel"      x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-startLevel"    x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-minLevel"      x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-dryRunLevel"   x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+    <line id="ps-leader-outflowLevel"  x1="0" y1="0" x2="0" y2="0" stroke="#bbb" stroke-width="0.6" stroke-dasharray="2 2" visibility="hidden" />
+
     <!-- Ordering-warning ribbon -->
-    <text id="ps-warning" x="260" y="410" text-anchor="middle" fill="#C0392B" font-size="10" font-style="italic" visibility="hidden"></text>
+    <text id="ps-warning" x="260" y="460" text-anchor="middle" fill="#C0392B" font-size="10" font-style="italic" visibility="hidden"></text>
   </svg>
 
   <div class="form-row">