feat: standalone web UI (React + Vite)

React + TypeScript UI on port 5274. Connects to local daemon via
WebSocket IPC (DaemonAdapter). Full chat layout with sidebar, message
pane, and peer list. Mirrors the TUI feature set.

- src/types.ts        — IPC types mirroring proto.go
- src/adapter/daemon  — WebSocket IPC adapter with auto-reconnect
- src/store/index.ts  — Zustand store; handles all daemon events
- src/pages/          — Onboarding (connect + join) and Chat
- src/components/     — Sidebar, MessagePane, PeerList

Dev: cd web && npm run dev  (port 5274)
Build: cd web && npm run build

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/src/types.ts

@@ -0,0 +1,104 @@
+// Types mirroring internal/proto — keep in sync with proto.go
+
+export type PeerID = string // 64-char lowercase hex
+
+export interface PeerInfo {
+  id: PeerID
+  alias: string
+  public_key: string
+  created_at: string
+}
+
+export interface NetworkInfo {
+  network_id: string
+  network_name: string
+  local_peer?: PeerInfo
+  share_dir?: string
+  download_dir?: string
+}
+
+export interface ChatMessage {
+  mid?: string
+  from: PeerID
+  to?: PeerID
+  room: string
+  text: string
+  ts: number // Unix ms
+}
+
+export interface FileEntry {
+  name: string
+  size_bytes: number
+}
+
+export interface FileOffer {
+  xid: string
+  name: string
+  size: number
+  sha256: string
+}
+
+// ── IPC message types ─────────────────────────────────────────────────────────
+
+export type IpcMsgType =
+  // commands
+  | 'send_message'
+  | 'join_network'
+  | 'leave_network'
+  | 'get_state'
+  | 'send_file'
+  | 'set_share_dir'
+  | 'generate_invite'
+  | 'get_file_list'
+  | 'export_identity'
+  | 'import_identity'
+  // events
+  | 'state_snapshot'
+  | 'message_received'
+  | 'peer_connected'
+  | 'peer_disconnected'
+  | 'session_ready'
+  | 'network_joined'
+  | 'network_left'
+  | 'file_list'
+  | 'file_progress'
+  | 'file_complete'
+  | 'incoming_file'
+  | 'invite_generated'
+  | 'identity_exported'
+  | 'identity_imported'
+  | 'error'
+
+export interface IpcMessage {
+  type: IpcMsgType
+  // routing
+  network_id?: string
+  // send_message
+  room?: string
+  to?: PeerID
+  body?: string
+  // join_network
+  network_name?: string
+  share_dir?: string
+  // send_file / set_share_dir
+  path?: string
+  peer_id?: PeerID
+  // identity
+  passphrase?: string
+  backup?: string
+  // events
+  peer?: PeerInfo
+  nick?: string
+  message?: ChatMessage
+  offer?: FileOffer
+  transfer_id?: string
+  bytes_received?: number
+  total_bytes?: number
+  local_peer?: PeerInfo
+  connected_peers?: PeerInfo[]
+  rooms?: string[]
+  networks?: NetworkInfo[]
+  error_message?: string
+  invite?: string
+  files?: FileEntry[]
+}