- Updated `TimestampMixin` to use `server_default` for `created_at` and `updated_at` fields.
- Modified various models in the `fa_classes`, `doc_types_dig`, `ports`, `units_of_measure`, `invoices`, `parts`, `trailers`, `licenses`, `tenants`, and `user_tenant` modules to set `server_default` for boolean fields and other relevant fields.
- Adjusted the `trailer_types` model to change the schema from `a76` to `public`.
- Implemented database migration execution during application startup in `main.py`.
- Removed old Alembic migration execution logic from the entrypoint script.
- Updated seed data for units of measure and removed unused seed files.
- Added endpoints for license management including creation, retrieval, update, validation, and usage tracking.
- Developed service layer for business logic related to licenses.
- Introduced tenant management APIs for creating, updating, listing, and deleting tenants.
- Implemented user-tenant relationship management with endpoints for adding, removing, and updating user roles in tenants.
- Created DTOs for data transfer between layers and models for ORM mapping.
- Enhanced logging and error handling across services.
