fix(api): import Base from models package to register all ORM tables

The models/__init__.py imports all ORM model classes (Store, Product,
Coupon, etc.) which registers their table definitions with Base.metadata.
Importing Base directly from models.base skips this registration, so
alembic's create_all() on fresh databases fails to create app tables.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

alembic/env.py

@@ -6,7 +6,7 @@ from logging.config import fileConfig
 from sqlalchemy import engine_from_config, pool
 
 from alembic import context
-from cartsnitch_api.models.base import Base  # noqa: F401 — imports all models for autogenerate
+from cartsnitch_api.models import Base  # noqa: F401 — imports all models for autogenerate
 
 config = context.config
 if config.config_file_name is not None: