Refactor database models to use server defaults for boolean and timestamp fields

- 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.

backend/api/v1/modules/a24/fa/fa_classes/models.py

@@ -18,18 +18,32 @@ class QClasses(Base, TenantScopedMixin, TimestampMixin):
     __tablename__ = "fa_classes"  # QClases
     __table_args__ = (
         PrimaryKeyConstraint("id", name="qclases_pk"),
-        ForeignKeyConstraint(["class_id"], ["a76.classes.id"], name="fk_qclasses_classes"),
+        ForeignKeyConstraint(
+            ["class_id"], ["a76.classes.id"], name="fk_qclasses_classes"
+        ),
         {"schema": "a24"},
     )
 
     id: Mapped[int] = mapped_column(Integer, primary_key=True)
     class_id: Mapped[int] = mapped_column(Integer, nullable=False)
 
-    import_tariff_code: Mapped[Optional[str]] = mapped_column(String(10), nullable=True)  # FRACCIONIMPO
-    import_tariff_type: Mapped[Optional[str]] = mapped_column(String(6), nullable=True)  # TIPOFRACIMPO
-    export_tariff_code: Mapped[Optional[str]] = mapped_column(String(10), nullable=True)  # FRACCIONEXPO
-    export_tariff_type: Mapped[Optional[str]] = mapped_column(String(6), nullable=True)  # TIPOFRACEXPO
-    depreciation_rate: Mapped[Optional[Decimal]] = mapped_column(Numeric(5, 2), nullable=True)  # TASADEPRECIA
+    import_tariff_code: Mapped[Optional[str]] = mapped_column(
+        String(10), nullable=True
+    )  # FRACCIONIMPO
+    import_tariff_type: Mapped[Optional[str]] = mapped_column(
+        String(6), nullable=True
+    )  # TIPOFRACIMPO
+    export_tariff_code: Mapped[Optional[str]] = mapped_column(
+        String(10), nullable=True
+    )  # FRACCIONEXPO
+    export_tariff_type: Mapped[Optional[str]] = mapped_column(
+        String(6), nullable=True
+    )  # TIPOFRACEXPO
+    depreciation_rate: Mapped[Optional[Decimal]] = mapped_column(
+        Numeric(5, 2), nullable=True
+    )  # TASADEPRECIA
     fda_code: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)  # FDA
     eccn_code: Mapped[Optional[str]] = mapped_column(String(20), nullable=True)  # ECCN
-    class_enabled: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)  # HABILITADESHABILITACLASE
+    class_enabled: Mapped[bool] = mapped_column(
+        Boolean, default=True, server_default="true", nullable=False
+    )  # HABILITADESHABILITACLASE