feat: add sources CRUD API with tests

- Full CRUD endpoints for backup sources
- Pydantic validation for source types
- pytest tests for create, list, get, delete

backend/app/routers/sources.py

@@ -0,0 +1,61 @@
+from fastapi import APIRouter, Depends, HTTPException
+from sqlalchemy.ext.asyncio import AsyncSession
+from sqlalchemy import select
+from typing import List
+from app.database import get_db
+from app.models import Source
+from app.schemas import SourceCreate, SourceUpdate, Source as SourceSchema
+
+router = APIRouter(prefix="/api/sources", tags=["sources"])
+
+@router.get("/", response_model=List[SourceSchema])
+async def list_sources(db: AsyncSession = Depends(get_db)):
+    result = await db.execute(select(Source))
+    sources = result.scalars().all()
+    return sources
+
+@router.post("/", response_model=SourceSchema)
+async def create_source(source: SourceCreate, db: AsyncSession = Depends(get_db)):
+    db_source = Source(**source.model_dump())
+    db.add(db_source)
+    await db.commit()
+    await db.refresh(db_source)
+    return db_source
+
+@router.get("/{source_id}", response_model=SourceSchema)
+async def get_source(source_id: int, db: AsyncSession = Depends(get_db)):
+    result = await db.execute(select(Source).where(Source.id == source_id))
+    source = result.scalar_one_or_none()
+    if not source:
+        raise HTTPException(status_code=404, detail="Source not found")
+    return source
+
+@router.put("/{source_id}", response_model=SourceSchema)
+async def update_source(
+    source_id: int,
+    source_update: SourceUpdate,
+    db: AsyncSession = Depends(get_db)
+):
+    result = await db.execute(select(Source).where(Source.id == source_id))
+    source = result.scalar_one_or_none()
+    if not source:
+        raise HTTPException(status_code=404, detail="Source not found")
+    
+    update_data = source_update.model_dump(exclude_unset=True)
+    for field, value in update_data.items():
+        setattr(source, field, value)
+    
+    await db.commit()
+    await db.refresh(source)
+    return source
+
+@router.delete("/{source_id}")
+async def delete_source(source_id: int, db: AsyncSession = Depends(get_db)):
+    result = await db.execute(select(Source).where(Source.id == source_id))
+    source = result.scalar_one_or_none()
+    if not source:
+        raise HTTPException(status_code=404, detail="Source not found")
+    
+    await db.delete(source)
+    await db.commit()
+    return {"message": "Source deleted"}