feat: embed AI travel chat in collection recommendations

CLAUDE.md

@@ -9,6 +9,7 @@
 - Use the API proxy pattern: never call Django directly from frontend components.
 - Route all frontend API calls through `frontend/src/routes/api/[...path]/+server.ts`.
 - Proxy target is `http://server:8000`; preserve session cookies and CSRF behavior.
+- AI chat is embedded in Collections → Recommendations via `AITravelChat.svelte`. There is no standalone `/chat` route. Chat providers are loaded dynamically from `GET /api/chat/providers/` (backed by LiteLLM runtime providers + custom entries like `opencode_zen`). Chat conversations stream via SSE through `/api/chat/conversations/`.
 - Service ports:
   - `web` → `:8015`
   - `server` → `:8016`
@@ -21,23 +22,25 @@
 ## Codebase Layout
 - Backend root: `backend/server/`
   - Apps: `adventures/`, `users/`, `worldtravel/`, `integrations/`, `achievements/`, `chat/`
+  - Chat provider config: `backend/server/chat/llm_client.py` (`CHAT_PROVIDER_CONFIG`)
 - Frontend root: `frontend/src/`
   - Routes: `src/routes/`
-  - Shared types: `src/lib/types.ts`
-  - Components: `src/lib/components/`
+  - Shared types: `src/lib/types.ts` (includes `ChatProviderCatalogEntry`)
+  - Components: `src/lib/components/` (includes `AITravelChat.svelte`)
   - Locales: `src/locales/`
 
 ## Development Workflow
 - Develop Docker-first. Start services with Docker before backend-dependent work.
 - Use these commands:
 
-### Frontend
-- `cd frontend && npm run format`
-- `cd frontend && npm run lint`
-- `cd frontend && npm run check`
-- `cd frontend && npm run build`
+### Frontend (prefer Bun)
+- `cd frontend && bun run format`
+- `cd frontend && bun run lint`
+- `cd frontend && bun run check`
+- `cd frontend && bun run build`
+- `cd frontend && bun install`
 
-### Backend
+### Backend (Docker required; prefer uv for local Python tooling)
 - `docker compose exec server python3 manage.py test`
 - `docker compose exec server python3 manage.py migrate`
 
@@ -47,15 +50,15 @@
 
 ## Pre-Commit Checklist
 Run in this exact order:
-1. `cd frontend && npm run format`
-2. `cd frontend && npm run lint`
-3. `cd frontend && npm run check`
-4. `cd frontend && npm run build`
+1. `cd frontend && bun run format`
+2. `cd frontend && bun run lint`
+3. `cd frontend && bun run check`
+4. `cd frontend && bun run build`
 
 **ALWAYS run format before committing.**
 
 ## Known Issues (Expected)
-- Frontend `npm run check`: **3 type errors + 19 warnings** expected
+- Frontend `bun run check`: **3 type errors + 19 warnings** expected
 - Backend tests: **2/3 fail** (expected)
 - Docker dev setup has frontend-backend communication issues (500 errors beyond homepage)
 
@@ -64,6 +67,8 @@ Run in this exact order:
 - API access: always use proxy route `/api/[...path]/+server.ts`
 - Styling: prefer DaisyUI semantic classes (`bg-primary`, `text-base-content`)
 - CSRF handling: use `/auth/csrf/` + `X-CSRFToken`
+- Chat providers: dynamic catalog from `GET /api/chat/providers/`; configured in `CHAT_PROVIDER_CONFIG`
 
 ## Conventions
 - Do **not** attempt to fix known test/configuration issues as part of feature work.
+- Use `bun` for frontend commands, `uv` for local Python tooling where applicable.