Phase 1: Foundation — backend auth, frontend shell, Docker setup

Backend (FastAPI):
- App factory with async SQLAlchemy 2.0 + PostgreSQL
- Alembic migration for users and sessions tables
- JWT auth (access + refresh tokens, bcrypt passwords)
- Auth endpoints: register, login, refresh, logout, me
- Admin seed script, role-based access deps

Frontend (React + TypeScript):
- Vite + Tailwind CSS + shadcn/ui theme (health-oriented palette)
- i18n with English and Russian translations
- Zustand auth/UI stores with localStorage persistence
- Axios client with automatic token refresh on 401
- Login/register pages, protected routing
- App layout: collapsible sidebar, header with theme/language toggles
- Dashboard with placeholder stats

Infrastructure:
- Docker Compose (postgres, backend, frontend, nginx)
- Nginx reverse proxy with WebSocket support
- Dev override with hot reload

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

backend/tests/conftest.py

@@ -0,0 +1,61 @@
+import asyncio
+import uuid
+from collections.abc import AsyncGenerator
+
+import pytest
+from httpx import ASGITransport, AsyncClient
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+
+from app.database import Base, get_db
+from app.main import create_app
+
+# Use a unique in-memory-like approach: create a separate test DB schema
+TEST_DATABASE_URL = "postgresql+asyncpg://ai_assistant:changeme@localhost:5432/ai_assistant_test"
+
+
+@pytest.fixture(scope="session")
+def event_loop():
+    loop = asyncio.new_event_loop()
+    yield loop
+    loop.close()
+
+
+@pytest.fixture(scope="session")
+async def test_engine():
+    engine = create_async_engine(TEST_DATABASE_URL)
+    async with engine.begin() as conn:
+        await conn.run_sync(Base.metadata.drop_all)
+        await conn.run_sync(Base.metadata.create_all)
+    yield engine
+    async with engine.begin() as conn:
+        await conn.run_sync(Base.metadata.drop_all)
+    await engine.dispose()
+
+
+@pytest.fixture
+async def db_session(test_engine) -> AsyncGenerator[AsyncSession, None]:
+    session_factory = async_sessionmaker(test_engine, class_=AsyncSession, expire_on_commit=False)
+    async with session_factory() as session:
+        yield session
+        await session.rollback()
+
+
+@pytest.fixture
+async def client(test_engine) -> AsyncGenerator[AsyncClient, None]:
+    session_factory = async_sessionmaker(test_engine, class_=AsyncSession, expire_on_commit=False)
+
+    async def override_get_db():
+        async with session_factory() as session:
+            try:
+                yield session
+                await session.commit()
+            except Exception:
+                await session.rollback()
+                raise
+
+    app = create_app()
+    app.dependency_overrides[get_db] = override_get_db
+
+    transport = ASGITransport(app=app)
+    async with AsyncClient(transport=transport, base_url="http://test") as ac:
+        yield ac