Updated `Base` import to use centralized `app.core.database.Base` for consistency. Enhanced `TimestampMixin` and `UUIDMixin` with docstrings for clarity. Fixed metadata reference in `guest_gifts` table and added relationships in `email_template`.
Rename metadata fields for clarity and fix imports.
Updated metadata-related field names across models to improve clarity and consistency (e.g., `metadata` to `media_metadata` and `notification_metadata`). Fixed an error in `guest_gifts` metadata reference and added a proper imports initialization in `__init__.py` for all models.
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Created reusable `Base`, `UUIDMixin`, and `TimestampMixin` in `base.py`. Added a `User` model with attributes, relationships, and database configurations in `user.py` to establish a foundation for user-related features.
