feat v1.42.0: room settings — the third settings tier

- four-tier principle fixed in ARCHITECTURE: global > space > room >
  device, specific overrides general, unset inherits
- room.settings { fill_mode, temp_source, hum_source } with backend
  schema; pure roomFillModeOf + sourceValue (+2 test suites, 114)
- gear on room cards in the Plan editor opens Room settings: rename,
  re-area (current area included in the list), fill override (may opt
  out of glow darkness), explicit temp/hum source with a searchable
  device+entity dropdown; the same section in the creation dialog
- source feeds the room card, tooltip and temp fill; works for rooms
  without an HA area (user-feedback case #1)
- smoke_room_settings.mjs (10 checks); TESTING/CHANGELOG/ARCHITECTURE
  same-commit

test/logic.test.mjs

@@ -11,6 +11,7 @@ import {
   alignGuides, segmentAngle, is45,
   swipeTarget, clampScale,
   migratePdfUrls,
+  roomFillModeOf,
   segmentCm, formatLength, roomEdges, roomPoly, pointOnBoundary, pointStrictlyInside, roomsOverlap,
   mergeRooms, splitRoom, polygonArea, closestPointOnBoundary, isActiveState, snapToWall, openingAmount, fillColorsOf, lerpColor, roomFillStyle, stateIcon, lightColorOf, isAlarmState, parseRoomRef, diffNewDevices,
 } from '../test-build/logic.js';
@@ -800,3 +801,11 @@ test('migratePdfUrls: rebinding rewrites file urls', () => {
   // без смены id — как есть
   assert.equal(migratePdfUrls(pdfs, 'x', 'x'), pdfs);
 });
+
+test('roomFillModeOf: tier-3 override beats the space, junk inherits', () => {
+  assert.equal(roomFillModeOf('temp', { settings: { fill_mode: 'light' } }), 'light');
+  assert.equal(roomFillModeOf('glow', { settings: { fill_mode: 'none' } }), 'none'); // выход из тьмы
+  assert.equal(roomFillModeOf('temp', {}), 'temp');
+  assert.equal(roomFillModeOf('temp', null), 'temp');
+  assert.equal(roomFillModeOf('temp', { settings: { fill_mode: 'glow' } }), 'temp'); // glow нельзя выбрать per-room
+});