fix(api): avoid distinct on json product fields in shopping suggestions

backend/innercontext/api/products.py

@@ -1082,12 +1082,12 @@ def suggest_shopping(session: Session = Depends(get_session)):
         raise HTTPException(status_code=502, detail=f"LLM returned invalid JSON: {e}")
 
     # Get products with inventory (those user already owns)
-    products_with_inventory = session.exec(
-        select(Product).join(ProductInventory).distinct()
+    products_with_inventory_ids = session.exec(
+        select(ProductInventory.product_id).distinct()
     ).all()
 
     shopping_context = ShoppingValidationContext(
-        owned_product_ids=set(p.id for p in products_with_inventory),
+        owned_product_ids=set(products_with_inventory_ids),
         valid_categories=set(ProductCategory),
         valid_targets=set(SkinConcern),
     )

backend/tests/test_products_helpers.py

@@ -87,6 +87,23 @@ def test_suggest_shopping(client, session):
     with patch(
         "innercontext.api.products.call_gemini_with_function_tools"
     ) as mock_gemini:
+        product = Product(
+            id=uuid.uuid4(),
+            short_id=str(uuid.uuid4())[:8],
+            name="Owned Serum",
+            brand="BrandX",
+            category="serum",
+            recommended_time="both",
+            leave_on=True,
+            product_effect_profile={},
+        )
+        session.add(product)
+        session.commit()
+        session.add(
+            ProductInventory(id=uuid.uuid4(), product_id=product.id, is_opened=True)
+        )
+        session.commit()
+
         mock_response = type(
             "Response",
             (),
@@ -94,7 +111,7 @@ def test_suggest_shopping(client, session):
                 "text": '{"suggestions": [{"category": "cleanser", "product_type": "cleanser", "priority": "high", "key_ingredients": [], "target_concerns": [], "why_needed": "reason", "recommended_time": "am", "frequency": "daily"}], "reasoning": "Test shopping"}'
             },
         )
-        mock_gemini.return_value = mock_response
+        mock_gemini.return_value = (mock_response, None)
 
         r = client.post("/products/suggest")
         assert r.status_code == 200