feat: full backend (untested)

backend/src/app/database.py

@@ -0,0 +1,13 @@
+from collections.abc import AsyncGenerator
+
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+
+from app.config import settings
+
+engine = create_async_engine(settings.database_url, echo=False)
+async_session_maker = async_sessionmaker(engine, expire_on_commit=False)
+
+
+async def get_db() -> AsyncGenerator[AsyncSession, None]:
+    async with async_session_maker() as session:
+        yield session