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

docs/ARCHITECTURE.md

@@ -243,3 +243,15 @@ hash falls back to the default.
   pipeline (`swipeTarget`), per-screen multipliers in `LS_KIOSK`.
 - **Nav persistence** (v1.38.2): `LS_NAV` stores {space, mode}; hash
   deep-link > saved > default_floor; stale-cache retry after the live load.
+
+
+## Settings tiers (owner's principle, 2026-07-26)
+
+Four levels: **global (config.settings) → space (space.settings) → room
+(room.settings) → device (marker.*)**. Duplicated options are deliberate: the
+more specific tier overrides the more general one; "unset" always means
+"inherit". Resolution lives in pure helpers (`spaceDisplayOf`,
+`roomFillModeOf`, `sourceValue`, `resolveTapAction`) — never inline in render.
+The UI will later be unified around this model; until then each tier keeps its
+own dialog (general settings gear / space gear / room-card gear / marker
+dialog).

docs/CHANGELOG.md

@@ -1,5 +1,19 @@
 # Changelog
 
+## v1.42.0 — 2026-07-26 (room settings — the third tier)
+- **Settings now have four tiers**: global → space → room → device; the more
+  specific tier overrides the more general one (owner's principle, fixed in
+  ARCHITECTURE). This release adds the ROOM tier.
+- Every room card in the Plan editor gained a **gear**: rename the room,
+  change its HA area, override the **fill type** for this room only (works
+  in glow spaces too — 'none' pulls the room out of the darkness), and pick
+  an explicit **temperature / humidity source** — any HA device or entity —
+  instead of the default room average. The source feeds the room card, the
+  tooltip and the temperature fill, and works for rooms without an HA area
+  (the user-feedback case: a custom template sensor bound to a room).
+- The same settings section appears in the room dialog right after closing a
+  contour.
+
 ## v1.41.2 — 2026-07-26
 - Fixed attached PDF manuals breaking after a marker is rebound to another
   device: the id changes, but the uploaded files stayed in the OLD id's

docs/TESTING.md

@@ -140,6 +140,13 @@ Run the *core flows* (marked ★ below) in each environment at least once per mi
       (explicit ripple color still wins); off/white lights unchanged [auto]
 - [ ] Alarm pulse (v1.27.0): leak/smoke/gas/CO/siren in 'on' pulse a red ring over any
       display mode; clears on 'off'; unavailable never alarms [auto]; reduced-motion static
+- [ ] Room settings, tier 3 (v1.42.0): a gear on every room card in the Plan
+      editor opens Room settings (name, HA area incl. the current one, fill
+      override, temp/hum source); the creation dialog has the same section;
+      fill override repaints only that room (incl. opting OUT of the glow
+      darkness); a temp/hum source (device or entity) feeds the room card,
+      tooltip and temperature fill — works for rooms without an HA area;
+      renaming/rebinding an existing room now possible [auto]
 - [ ] PDF survival on rebinding (v1.41.2): rebind a marker with attached
       PDFs to another device — the server moves /files/<oldId>/ to the new id
       and the links keep opening; the old folder disappears (no orphans) [auto]