fix: move DASHBOARD_HTML to module level (was unreachable after run_app)

feat: universal multi-app proxy - streaming, cookie rewrite, body URL rewrite, WS subprotocol, auto-detect dashboard

fix: strip accept-encoding + install brotli to prevent 502 on multi-port proxy

fix: JupyterLab base_url=/8888/ + rewrite Location headers for redirects

feat: multi-port proxy - dashboard + any port routing

perf: shared ClientSession with connection pooling + in-memory static cache

fix: remove environment= from supervisord to preserve HF secrets (password)

Auto-detect ALL WebSocket upgrades (fixes /api/events/subscribe, terminals, kernels)

Fix 502 on /lab: use aiohttp.ClientTimeout instead of invalid timeout_class

Fix ImportError: import WSMsgType from aiohttp (top-level), not aiohttp.client

Fix proxy.py: route order (WS before catch-all), robust error handling, no type hints

Replace nginx+flask auth with single aiohttp proxy (fix JS chunks getting HTML 302)