Phase 1 MVP: gateway, CRUD handlers, frontend components

Backend:
- WebSocket gateway (hub, client, events) with fanout broadcast
- Server CRUD handlers (create, list, get, update, delete)
- Channel CRUD handlers (create, list, get, update, delete)
- Message CRUD handlers (list with cursor pagination, create, update, delete)
- cmd/migrate standalone migration CLI (up/down)
- cmd/server wired to all handlers + WebSocket + static file serving

Frontend:
- Zustand stores: auth, server, channel, message, websocket
- API client with fetch wrapper
- Terminal-styled components: Layout, LoginForm, ChatArea, ChannelList, ServerBar, MemberList
- React Router with login and main routes
- Gruvbox dark palette throughout

Ops:
- Docker Compose with app service (multi-stage build)
- Caddyfile with WebSocket upgrade support
- Makefile for common tasks

go.sum

@@ -5,6 +5,8 @@ github.com/go-chi/chi/v5 v5.3.0 h1:halUjDxhshgXHMrao5bB8eNBXo/rnzwr8m5m36glehM=
 github.com/go-chi/chi/v5 v5.3.0/go.mod h1:R+tYY2hNuVUUjxoPtqUdgBqevM9s9njzkTLutVsOCto=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
+github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
 github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
 github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=