feat: task 2.1 MapView singleton + mapReady gate

- pnpm add maplibre-gl + -D @types/geojson.
- src/map/core/styles.ts: defaultStyle (OSM raster bootstrap; 2.2
  replaces with the basemap-switcher descriptor table).
- src/map/core/map-view.tsx: module-level Map singleton lazily created
  on first <MapView> mount, attached to a class="trm-map-host" detached
  <div> that React refs append/remove on mount/unmount. Style-data
  lifecycle flips mapReady false on every styledata event, polls
  loaded() at 33ms intervals, flips ready true once the style is
  loaded — the canonical MapLibre style-swap dance.
- Exports getMap()/getMapReady()/subscribeMapReady()/useMapReady (via
  useSyncExternalStore for SSR-safe + concurrent-safe reads). getMap()
  throws if called pre-mount; the explicit failure mode beats a
  null-able top-level export.
- src/routes/_authed/monitor.tsx: new /monitor route, full-viewport
  <MapView /> for 2.1 (no children — subsequent tasks plug in here).
- src/routes/_authed/index.tsx: home-page card now links to /monitor.
- eslint.config.js: override for src/map/** + src/live/** disables
  react-refresh/only-export-components. Same pattern as the existing
  overrides for shadcn primitives and route files.

Deviation: spec sketched a top-level `map` constant export; implemented
as `getMap(): MapLibreMap` (a function) so the singleton stays lazy
until <MapView> mounts. Top-level constant would either force eager
init (breaks SSR/tests) or be nullable (footgun). The function form
throws a clear error if called pre-mount.

Bundle: /monitor lazy chunk is 1MB raw / 274KB gzipped (MapLibre + CSS).
Other routes unaffected. Vite chunk-size warning is harmless.

.planning/phase-2-live-map/07-event-picker.md

@@ -14,6 +14,7 @@ After this task, the live map is operator-driven — no hardcoded event id, no d
 ## Deliverables
 
 - **`src/data/events.ts`** — TanStack Query hook + types:
+
   ```ts
   export type EventSummary = {
     id: string;
@@ -27,7 +28,9 @@ After this task, the live map is operator-driven — no hardcoded event id, no d
 
   export function useUserEvents(): UseQueryResult<EventSummary[]>;
   ```
+
   Fetches `/items/events?fields=id,name,slug,discipline,starts_at,ends_at,organization_id&sort=-starts_at`. Directus's RLS handles "what events does this user have access to" via the cookie. Stale time 5 minutes.
+
 - **`src/ui/components/event-picker.tsx`** — `<EventPicker />` component. Top-of-page dropdown showing the events list. Selected event highlights. On select, calls a callback (passed in by the monitor route).
 - **`src/routes/_authed/monitor.tsx`** updated — orchestrates the picker → subscribe → snapshot → store flow:
   ```tsx
@@ -46,7 +49,7 @@ After this task, the live map is operator-driven — no hardcoded event id, no d
           <MapSelectedDevice />
         </MapView>
         <BasemapSwitcher />
-        <ConnectionChip />   {/* 2.9 */}
+        <ConnectionChip /> {/* 2.9 */}
       </>
     );
   }
@@ -107,27 +110,30 @@ export function useActiveEventOrchestration() {
   const clearStore = usePositionStore((s) => s.clearForEvent);
   const activeEventId = usePositionStore((s) => s.activeEventId);
 
-  return useCallback(async (eventId: string | null) => {
-    const client = getLiveClient();
+  return useCallback(
+    async (eventId: string | null) => {
+      const client = getLiveClient();
 
-    // Tear down the previous subscription.
-    if (activeEventId) {
-      await client.unsubscribe(`event:${activeEventId}`).catch(() => {});
-      clearStore();
-    }
+      // Tear down the previous subscription.
+      if (activeEventId) {
+        await client.unsubscribe(`event:${activeEventId}`).catch(() => {});
+        clearStore();
+      }
 
-    if (!eventId) return;
+      if (!eventId) return;
 
-    // Subscribe to the new one.
-    const result = await client.subscribe(`event:${eventId}`);
-    if (!result.ok) {
-      // Surface to UI (toast or inline error).
-      console.warn('subscribe failed', result);
-      return;
-    }
-    setActiveEventInStore(eventId, result.snapshot);
-    localStorage.setItem('trm-active-event-id', eventId);
-  }, [activeEventId, clearStore, setActiveEventInStore]);
+      // Subscribe to the new one.
+      const result = await client.subscribe(`event:${eventId}`);
+      if (!result.ok) {
+        // Surface to UI (toast or inline error).
+        console.warn('subscribe failed', result);
+        return;
+      }
+      setActiveEventInStore(eventId, result.snapshot);
+      localStorage.setItem('trm-active-event-id', eventId);
+    },
+    [activeEventId, clearStore, setActiveEventInStore],
+  );
 }
 ```