feat(core): register Attachment model

app/models/__init__.py

@@ -8,6 +8,7 @@ from app.models.currency import Currency
 from app.models.tax import TaxRate
 from app.models.sequence import Sequence
 from app.models.system_settings import SystemSettings
+from app.models.attachment import Attachment
 from app.models.notification import Notification
 from app.models.plugin import Plugin, PluginMigration
 from app.models.role import Role
@@ -33,6 +34,8 @@ __all__ = [
     "TaxRate",
     "Sequence",
     "SystemSettings",
+    "Attachment",
+    "Attachment",
     "SystemSettings",
     "Sequence",
     "TaxRate",