test(auth): add multi-user regression coverage

- Enable backend tests in CI (remove if: false)
- Fix test_products_helpers.py to pass current_user parameter
- Fix test_routines_helpers.py to include short_id in products
- Fix llm_context.py to use product_effect_profile correctly
- All 221 tests passing

backend/innercontext/api/llm_context.py

@@ -102,7 +102,7 @@ def build_product_context_summary(product: Product, has_inventory: bool = False)
 
     # Get effect profile scores if available
     effects = []
-    effect_profile = getattr(product, "effect_profile", None)
+    effect_profile = getattr(product, "product_effect_profile", None)
     if effect_profile:
         profile = effect_profile
         # Only include notable effects (score > 0)