feat(auth): replace cookie/api-key auth with JWT Bearer tokens, separate UI from API

- Add JWT Bearer token validation to Rust API via OIDC provider JWKS
  with automatic key rotation and 1-hour cache
- Remove x-api-key auth support and built-in web UI from furumi-web-player,
  leaving it as a pure API server
- Add /auth/token endpoint to Node player server to expose OIDC access
  tokens to the frontend
- Move Node player auth endpoints from /api/* to /auth/* to avoid
  path conflicts with Rust API
- Add static file serving to Node Express server for production
  single-container deployment
- Fix SameSite=Strict cookie issue breaking OIDC redirect flow (use Lax)
- Add Dockerfile.node-player with multi-stage Node.js build
- Add CI workflows for node-player Docker image (dev + release)
- Optimize Rust Dockerfiles with dependency caching layer
- Update docker-compose with OIDC env vars and OLLAMA_MODEL support
- Cherry-pick agent LLM client fixes from DEV branch

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker/Dockerfile.node-player

@@ -0,0 +1,38 @@
+FROM node:22-alpine AS build
+
+WORKDIR /app
+
+# 1. Install server dependencies (cached layer)
+COPY furumi-node-player/server/package.json furumi-node-player/server/package-lock.json ./server/
+RUN cd server && npm ci
+
+# 2. Install client dependencies (cached layer)
+COPY furumi-node-player/client/package.json furumi-node-player/client/package-lock.json ./client/
+RUN cd client && npm ci
+
+# 3. Build server
+COPY furumi-node-player/server/ ./server/
+RUN cd server && npm run build
+
+# 4. Build client (VITE_FURUMI_API_URL empty = relative /api on same origin)
+COPY furumi-node-player/client/ ./client/
+RUN cd client && npm run build
+
+FROM node:22-alpine
+
+WORKDIR /app
+
+# Server runtime
+COPY --from=build /app/server/dist ./server/dist
+COPY --from=build /app/server/node_modules ./server/node_modules
+COPY --from=build /app/server/package.json ./server/
+
+# Client static files
+COPY --from=build /app/client/dist ./client/dist
+
+ENV NODE_ENV=production
+ENV PORT=3001
+
+EXPOSE 3001
+
+CMD ["node", "server/dist/index.js"]