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/commands/index.js

@@ -0,0 +1,50 @@
+'use strict';
+
+// pumpingStation command registry. Consumed by BaseNodeAdapter via
+// `static commands = require('./commands')`. Each descriptor maps a
+// canonical msg.topic to its handler; legacy names are listed under
+// `aliases` and emit a one-time deprecation warning at runtime.
+
+const handlers = require('./handlers');
+
+module.exports = [
+  {
+    topic: 'set.mode',
+    aliases: ['changemode'],
+    payloadSchema: { type: 'string' },
+    handler: handlers.setMode,
+  },
+  {
+    topic: 'child.register',
+    aliases: ['registerChild'],
+    // payload is the Node-RED id (string) of the child node.
+    payloadSchema: { type: 'string' },
+    handler: handlers.registerChild,
+  },
+  {
+    topic: 'cmd.calibrate.volume',
+    aliases: ['calibratePredictedVolume'],
+    // any: payload may be a number or numeric string.
+    payloadSchema: { type: 'any' },
+    handler: handlers.calibrateVolume,
+  },
+  {
+    topic: 'cmd.calibrate.level',
+    aliases: ['calibratePredictedLevel'],
+    payloadSchema: { type: 'any' },
+    handler: handlers.calibrateLevel,
+  },
+  {
+    topic: 'set.inflow',
+    aliases: ['q_in'],
+    // any: number, numeric string, or { value, unit, timestamp } object.
+    payloadSchema: { type: 'any' },
+    handler: handlers.setInflow,
+  },
+  {
+    topic: 'set.demand',
+    aliases: ['Qd'],
+    payloadSchema: { type: 'any' },
+    handler: handlers.setDemand,
+  },
+];