Phase 1: auth, room CRUD, WebSocket chat, PWA frontend

Invite-only FastAPI + SQLAlchemy(async) + Postgres backend (session-cookie
auth via CLI-provisioned accounts, open-room CRUD, single-instance /ws/chat)
and a React + Vite PWA frontend (login, room list, chat view). Backend tests
pass against a local Postgres DB. See README.md and backend/README.md for
setup, and ARCHITECTURE.md for the full phased design.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/api/auth.ts

@@ -0,0 +1,21 @@
+import { apiFetch } from './client'
+import type { User } from '../types'
+
+// No register() here: this is an invite-only site. Accounts are created by
+// an operator via the backend CLI (`python -m app.cli create-user`), not
+// through a public endpoint.
+
+export function login(usernameOrEmail: string, password: string): Promise<User> {
+  return apiFetch<User>('/api/auth/login', {
+    method: 'POST',
+    body: JSON.stringify({ username_or_email: usernameOrEmail, password }),
+  })
+}
+
+export function logout(): Promise<void> {
+  return apiFetch<void>('/api/auth/logout', { method: 'POST' })
+}
+
+export function me(): Promise<User> {
+  return apiFetch<User>('/api/auth/me')
+}

frontend/src/api/client.ts

@@ -0,0 +1,33 @@
+export class ApiError extends Error {
+  status: number
+
+  constructor(status: number, message: string) {
+    super(message)
+    this.status = status
+  }
+}
+
+export async function apiFetch<T>(path: string, init?: RequestInit): Promise<T> {
+  const response = await fetch(path, {
+    credentials: 'include',
+    headers: { 'Content-Type': 'application/json' },
+    ...init,
+  })
+
+  if (!response.ok) {
+    let detail = response.statusText
+    try {
+      const body = await response.json()
+      detail = body.detail ?? detail
+    } catch {
+      // response had no JSON body
+    }
+    throw new ApiError(response.status, detail)
+  }
+
+  if (response.status === 204) {
+    return undefined as T
+  }
+
+  return (await response.json()) as T
+}

frontend/src/api/rooms.ts

@@ -0,0 +1,21 @@
+import { apiFetch } from './client'
+import type { Message, Room, RoomListItem } from '../types'
+
+export function listRooms(): Promise<RoomListItem[]> {
+  return apiFetch<RoomListItem[]>('/api/rooms')
+}
+
+export function createRoom(name: string, description?: string): Promise<Room> {
+  return apiFetch<Room>('/api/rooms', {
+    method: 'POST',
+    body: JSON.stringify({ name, description: description || null }),
+  })
+}
+
+export function joinRoom(roomId: string): Promise<Room> {
+  return apiFetch<Room>(`/api/rooms/${roomId}/join`, { method: 'POST' })
+}
+
+export function getRoomMessages(roomId: string): Promise<Message[]> {
+  return apiFetch<Message[]>(`/api/rooms/${roomId}/messages`)
+}