V71: Rename product_ids → product_uuids in shop import logs.

The shop module has migrated from integer primary keys to UUIDs. The product_ids column (integer[]) held UUID values incorrectly typed; this migration replaces it with a proper product_uuids uuid[] column.

Changes

• Add product_uuids uuid[] DEFAULT '{}' to phoenix_kit_shop_import_logs
• Drop product_ids integer[] from phoenix_kit_shop_import_logs

All operations are idempotent (guarded by table/column existence checks).