fix: follow Home Assistant Area marker moves

Issue: #126
User-Visible: yes

scripts/config-field-registry.mjs

@@ -85,6 +85,21 @@ export const CONFIG_FIELD_REGISTRY = Object.freeze([
     migration: 'drop on the next settings save',
     compatibility: 'backend accepts bounded values so old configs still load',
   },
+  {
+    id: 'settings.marker_area_snapshot',
+    enforcedBy: 'device-area-relocation.ts + validation.py; #126',
+    selector: { path: ['settings', 'marker_area_snapshot'] },
+    storage: 'House Plan server config',
+    type: 'Record<markerId, { binding: device:* | entity:*, area: areaId }>',
+    default: 'unset (= one-time safe backfill)',
+    level: 'global internal lifecycle metadata',
+    ui: 'hidden',
+    runtime: 'detect authoritative HA Area changes and supersede stale saved positions',
+    introduced: '#126 / v1.70.0',
+    status: 'current',
+    migration: 'safe point-in-room backfill; cross-source full import drops it',
+    compatibility: 'older frontends ignore it; same-source backup preserves it',
+  },
   {
     id: 'markers[].display=ripple',
     enforcedBy: 'logic.ts normalizeDeviceDisplay (read) + editor-runtime _dropLegacySegments rewrites on every write',

scripts/config-schema.json

@@ -380,6 +380,22 @@
       "maxLength": 500,
       "type": "str"
     },
+    "config.settings.marker_area_snapshot": {
+      "required": false
+    },
+    "config.settings.marker_area_snapshot.<All(<class 'str'>, Length(min=1, max=500), msg=None)>.area": {
+      "maxLength": 500,
+      "minLength": 1,
+      "required": true,
+      "type": "str"
+    },
+    "config.settings.marker_area_snapshot.<All(<class 'str'>, Length(min=1, max=500), msg=None)>.binding": {
+      "maxLength": 500,
+      "minLength": 1,
+      "opaque": "Match('^(?:device|entity):.+$', msg=None)",
+      "required": true,
+      "type": "str"
+    },
     "config.settings.new_device_ids": {
       "required": false
     },