```

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.
```

backend/app/models/__init__.py

@@ -0,0 +1,41 @@
+"""
+Models package initialization.
+Imports all models to ensure they're registered with SQLAlchemy.
+"""
+from .base import Base, TimestampMixin, UUIDMixin
+
+# Import user model
+from .user import User
+
+# Import event-related models
+from .event import Event
+from .event_manager import EventManager, EventManagerRole, init_event_owner
+from .event_theme import EventTheme
+from .event_media import EventMedia, MediaType, MediaPurpose
+
+# Import guest and RSVP models
+from .guest import Guest, GuestStatus, guest_gifts
+from .rsvp import RSVP, RSVPStatus
+
+# Import gift-related models
+from .gift import (
+    GiftItem, GiftStatus, GiftPriority, GiftCategory,
+    GiftPurchase
+)
+
+# Import new models
+from .email_template import EmailTemplate, TemplateType
+from .notification_log import NotificationLog, NotificationType, NotificationStatus
+from .activity_log import ActivityLog, ActivityType
+
+# Make sure all models are imported above this line
+__all__ = [
+    'Base', 'TimestampMixin', 'UUIDMixin',
+    'User',
+    'Event', 'EventManager', 'EventManagerRole', 'EventTheme', 'EventMedia',
+    'Guest', 'GuestStatus', 'RSVP', 'RSVPStatus',
+    'GiftItem', 'GiftStatus', 'GiftPriority', 'GiftCategory', 'GiftPurchase',
+    'EmailTemplate', 'TemplateType',
+    'NotificationLog', 'NotificationType', 'NotificationStatus',
+    'ActivityLog', 'ActivityType',
+]