feat: auto-scrape on product creation and update product data (Step 4)

- Add automatic scraping when creating a new product
- Update product title and image from scraped data
- Add GET /products/{id}/snapshots endpoint for price history
- Add list_snapshots and get_latest_snapshot to CRUD

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/api/routes_products.py

@@ -1,10 +1,11 @@
 from __future__ import annotations
 
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, BackgroundTasks, Depends, HTTPException, status
 from sqlalchemy.orm import Session
 
 from backend.app.api.deps import get_db
 from backend.app.db import crud, schemas
+from backend.app.scraper.runner import scrape_product
 
 router = APIRouter(prefix="/products", tags=["products"])
 
@@ -16,9 +17,15 @@ def list_products(skip: int = 0, limit: int = 50, db: Session = Depends(get_db))
 
 
 @router.post("", response_model=schemas.ProductRead, status_code=status.HTTP_201_CREATED)
-def create_product(payload: schemas.ProductCreate, db: Session = Depends(get_db)) -> schemas.ProductRead:
-    # création de produit rigoureuse via Pydantic
-    return crud.create_product(db, payload)
+def create_product(
+    payload: schemas.ProductCreate,
+    background_tasks: BackgroundTasks,
+    db: Session = Depends(get_db),
+) -> schemas.ProductRead:
+    product = crud.create_product(db, payload)
+    # Déclenche automatiquement le scraping après création
+    background_tasks.add_task(scrape_product, product.id)
+    return product
 
 
 @router.get("/{product_id}", response_model=schemas.ProductRead)
@@ -45,3 +52,15 @@ def delete_product(product_id: int, db: Session = Depends(get_db)) -> None:
         raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Produit introuvable")
     # suppression définitive en base
     crud.remove_product(db, product)
+
+
+@router.get("/{product_id}/snapshots", response_model=list[schemas.ProductSnapshotRead])
+def list_snapshots(
+    product_id: int,
+    limit: int = 30,
+    db: Session = Depends(get_db),
+) -> list[schemas.ProductSnapshotRead]:
+    product = crud.get_product(db, product_id)
+    if not product:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Produit introuvable")
+    return crud.list_snapshots(db, product_id, limit=limit)