feat: GeoScene frontend POC + Docker deploy for remote host

Migrate maps to @geoscene/core, polish monitoring/alerts UX, fix timeline
basemap flicker and district alert regions, and ship compose/nginx Docker
deploy assets with CBPOA_ROOT data mounts.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/CLAUDE.md

@@ -1,19 +1,21 @@
-# Frontend — React + TypeScript + Leaflet
+# Frontend — React + TypeScript + GeoScene Maps SDK
 
 ## Stack
 
 - React 18, TypeScript 5, Vite 5
 - Tailwind CSS, Recharts, Zustand (state), Axios
-- Leaflet / react-leaflet (maps)
+- `@geoscene/core` (Maps SDK for JavaScript) — POC uses Tianditu basemap + local GeoJSON / FastAPI risk tiles
 - Playwright (e2e tests)
 
 ## Structure
 
 ```
 frontend/src/
-  main.tsx              # Entry point
+  main.tsx              # Entry (+ GeoScene theme CSS)
   App.tsx               # Router setup
+  geoscene/             # MapView helpers + layer factories
   components/           # Reusable UI (maps, charts, nav)
+  legacy/               # Unused former Leaflet map experiments
   pages/                # Route-level views
   services/api.ts       # Axios client with TTL cache + request dedup
   stores/               # Zustand stores
@@ -28,15 +30,21 @@ frontend/src/
 ## Patterns
 
 - Components: PascalCase, one per file, default export
-- API calls: use `services/api.ts` wrappers (`riskApi`, `alertApi`, `caseApi`, `gridApi`) — they handle caching and request dedup
-- State: Zustand stores in `stores/`, typed with TypeScript interfaces from `types/`
-- Styling: Tailwind utility classes, no CSS modules
+- Map components: imperative `@geoscene/core` via `createMapView` — do not pass MapView instances between components
+- Coordinates: GeoScene uses `[longitude, latitude]`
+- API calls: use `services/api.ts` wrappers (`riskApi`, `alertApi`, `caseApi`, `gridApi`)
+- State: Zustand stores in `stores/`
+- Styling: Tailwind utility classes
+
+## Env (optional Enterprise later)
+
+See `.env.example` for `VITE_GEOSCENE_PORTAL_URL` / `VITE_LAYER_*`. POC runs without them.
 
 ## Running
 
 ```bash
 cd frontend
-pnpm dev          # localhost:5173, proxies /api → localhost:8000
+pnpm dev          # localhost:3000, proxies /api → localhost:8000
 pnpm build        # tsc + vite build → dist/
 ```
 
@@ -47,3 +55,4 @@ pnpm build        # tsc + vite build → dist/
 - Don't mix data fetching with presentation — fetch in pages, render in components
 - Don't inline styles when Tailwind classes work
 - Don't create god components (>200 lines) — extract sub-components
+- Don't reintroduce Leaflet or role/perspective switchers