Finish MVP and dockerize

apps/backend/fastapi/app/db/base.py

@@ -0,0 +1,8 @@
+from sqlalchemy.orm import DeclarativeBase
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+from app import models  # noqa: E402,F401

apps/backend/fastapi/app/db/session.py

@@ -0,0 +1,29 @@
+from __future__ import annotations
+
+from contextlib import asynccontextmanager
+
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+
+from app.core.config import get_settings
+from app.db.base import Base
+
+
+settings = get_settings()
+engine = create_async_engine(
+    settings.database_url, echo=settings.environment == "local", future=True
+)
+AsyncSessionLocal = async_sessionmaker(
+    bind=engine, expire_on_commit=False, class_=AsyncSession
+)
+
+
+@asynccontextmanager
+async def lifespan(app):  # pragma: no cover
+    async with engine.begin() as conn:
+        await conn.run_sync(Base.metadata.create_all)
+    yield
+
+
+async def get_session() -> AsyncSession:
+    async with AsyncSessionLocal() as session:
+        yield session