feat: task 2.9 connection status + per-device staleness fade — Phase 2 done

- src/live/last-seen.ts: formatLastSeen(ts, now) — "now" / "Ns ago" /
  "Nm ago" / "HH:MM".
- src/live/use-staleness.ts: useStalenessTick(intervalMs=1000) hook
  re-renders subscribers every interval with the current epoch ms.
- src/ui/components/connection-chip.tsx: <ConnectionChip /> bottom-left,
  three states (connected / connecting+reconnecting / disconnected),
  aria-live polite + role status.
- src/map/layers/map-positions.tsx: every FeatureProps now carries
  staleSec; both symbol layers interpolate icon-opacity (and text-opacity
  on the non-selected layer) on staleSec — 0-60s full opacity,
  5min faded, 30min very faded. Update effect rebuilds features at the
  staleness tick rate (1Hz).
- src/routes/_authed/monitor.tsx: renders <ConnectionChip />.
- src/live/index.ts: re-exports formatLastSeen + useStalenessTick.

Strategy A (faded marker via interpolation) chosen over Strategy B
(separate warning-badge layer) per the task's open-question
resolution; simpler and easier to extend later.

Deviations:
1. stalenessTick is its own hook in src/live/use-staleness.ts rather
   than a property on the position store — keeps the store clean of
   UI-driven re-render concerns; the hook is reusable.
2. <DeviceLastSeen deviceId> standalone component skipped — the SPA
   doesn't have a sidebar yet (Phase 3.4); the per-marker fade IS the
   indicator for v1.

Bundle: main 396KB / 121KB gz — small bump from 2.8.

🎉 Phase 2 — Live monitoring map — complete. All 9 tasks shipped.
End-to-end: login -> /monitor -> event auto-selects -> snapshot
positions render -> live updates flow via WS through the rAF
coalescer -> staleness fades stale markers -> connection chip
surfaces WS state. Dogfood-blocking work for Rally Albania 2026 done.

.planning/phase-2-live-map/08-camera-trio.md

@@ -192,7 +192,7 @@ Click toggles `mapFollow`. Selecting a device with follow off still pans to it o
 ## Done
 
 - **`src/map/core/map-pref-store.ts`** — added `mapFollow: boolean` (default `true`) + `setMapFollow`. Persisted via the existing `trm-map-prefs` zustand+persist store.
-- **`src/map/core/camera/default-camera.tsx`** — `<MapDefaultCamera />`. Watches `activeEventId` + `latestByDevice`. Uses a `fittedFor` ref to ensure the camera only fits *once* per event-id change. Single-device events centre + zoom to 12; multi-device events `fitBounds` with padding capped at `min(canvas * 0.1, 80)`.
+- **`src/map/core/camera/default-camera.tsx`** — `<MapDefaultCamera />`. Watches `activeEventId` + `latestByDevice`. Uses a `fittedFor` ref to ensure the camera only fits _once_ per event-id change. Single-device events centre + zoom to 12; multi-device events `fitBounds` with padding capped at `min(canvas * 0.1, 80)`.
 - **`src/map/core/camera/selected-device.tsx`** — `<MapSelectedDevice />`. Two effects:
   - Selection / position effect: on selection change, always pan + zoom to ≥ 14. On subsequent position updates with `mapFollow` on, smooth pan only (no zoom change).
   - Manual-pan listener: hooks `map.on('movestart', ...)`. Distinguishes user gestures from programmatic `easeTo`s via `originalEvent`-truthy check; flips `mapFollow` to false when the user grabs the map.
@@ -207,6 +207,7 @@ Click toggles `mapFollow`. Selecting a device with follow off still pans to it o
 - `<MapDefaultCamera>` clears `fittedFor.current = null` when `activeEventId` becomes null (e.g. on logout / event clear). Without that, switching back to the same event later wouldn't re-fit. Spec didn't call this out; added it as a small correctness fix.
 
 **Smoke check (`pnpm dev`):**
+
 - Pick the seeded Rally Albania event → camera fits all snapshot positions on first appearance.
 - Click a device → camera pans + zooms in.
 - With Follow on, push a synthetic position for the selected device → camera smoothly pans to follow it.