P2 wave 1: extract concerns from pumpingStation specificClass

Splits pumpingStation/src/ into focused concern modules. specificClass.js
will be slimmed to an orchestrator in P2.9 (integration); for now both
the inlined logic AND the new modules coexist so tests stay green
throughout.

  src/basin/         BasinGeometry + thresholdValidator (pure)
  src/measurement/   flowAggregator + measurementRouter + calibration
  src/control/       levelBased + flowBased(stub) + manual + index dispatcher
  src/safety/        safetyController split into dryRun + overfill rules
  src/commands/      registry array + handlers (canonical names from start)
  src/editor.js      260 lines of SVG basin-diagram redraw, was inline in .html
  examples/standalone-demo.js  was if(require.main===module) at bottom of specificClass.js
  CONTRACT.md        canonical inputs + outputs + emitted events

Modified:
  src/specificClass.js  removed the 170-line standalone demo block
  pumpingStation.html   oneditprepare/oneditsave delegate to editor.{init,save}
  pumpingStation.js     added admin endpoint serving src/editor.js

102 basic tests pass (60 new + 42 existing).
specificClass.js itself is unchanged in behaviour — integration is P2.9.

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

src/basin/thresholdValidator.js

@@ -0,0 +1,57 @@
+// Threshold-ordering validator for the pumpingStation basin + control +
+// safety config. Pure: returns the issues array, never logs or throws.
+// The caller decides what to do (warn, surface to status badge, fail tests).
+//
+// Invariants enforced (level-space, bottom → top):
+//   0 < outflowLevel < inflowLevel < overflowLevel ≤ basinHeight
+//   dryRunLevel ≤ minLevel ≤ startLevel < maxLevel ≤ overfillLevel
+//
+// dryRunLevel and overfillLevel are DERIVED from safety percentages — the
+// validator recomputes them so a config that places minLevel below the
+// effective dry-run trigger (a no-op control band) is caught here.
+
+/**
+ * @param {object} basin - BasinGeometry instance OR plain {inflowLevel, outflowLevel, overflowLevel, heightBasin, minHeightBasedOn}
+ * @param {object} levelbased - config.control.levelbased ({ minLevel, startLevel, maxLevel })
+ * @param {object} safety - config.safety ({ dryRunThresholdPercent, overfillThresholdPercent })
+ * @returns {Array<{aName, a, op, bName, b, msg}>}
+ */
+function validateThresholdOrdering(basin, levelbased, safety) {
+  const lvl = levelbased || {};
+  const sfy = safety || {};
+
+  const dryRunPct = Number(sfy.dryRunThresholdPercent) || 0;
+  const overfillPct = Number(sfy.overfillThresholdPercent) || 100;
+  const refLowLevel = basin.minHeightBasedOn === 'inlet' ? basin.inflowLevel : basin.outflowLevel;
+  const dryRunLevel = refLowLevel * (1 + dryRunPct / 100);
+  const overfillLevel = basin.overflowLevel * (overfillPct / 100);
+
+  const checks = [
+    ['outflowLevel',  basin.outflowLevel,  '<',  'inflowLevel',   basin.inflowLevel],
+    ['inflowLevel',   basin.inflowLevel,   '<',  'overflowLevel', basin.overflowLevel],
+    ['overflowLevel', basin.overflowLevel, '<=', 'basinHeight',   basin.heightBasin],
+    ['dryRunLevel',   dryRunLevel,         '<=', 'minLevel',      lvl.minLevel],
+    ['minLevel',      lvl.minLevel,        '<=', 'startLevel',    lvl.startLevel],
+    ['startLevel',    lvl.startLevel,      '<',  'maxLevel',      lvl.maxLevel],
+    ['maxLevel',      lvl.maxLevel,        '<=', 'overfillLevel', overfillLevel],
+  ];
+
+  const issues = [];
+  for (const [aName, a, op, bName, b] of checks) {
+    if (!Number.isFinite(a) || !Number.isFinite(b)) continue;
+    const ok = op === '<' ? a < b : a <= b;
+    if (!ok) {
+      issues.push({
+        aName,
+        a,
+        op,
+        bName,
+        b,
+        msg: `Threshold invariant violated: ${aName} (${a}) must be ${op} ${bName} (${b})`,
+      });
+    }
+  }
+  return issues;
+}
+
+module.exports = { validateThresholdOrdering };