Summary

• Deleting a user via OrgService.delete_member() failed with a NOT NULL constraint violation on access_token.user_id (and
  other child FKs like user_role_assignment.user_id)
• SQLAlchemy's default behavior when deleting a parent row is to SET NULL on child foreign keys to de-associate them — but
  these columns are non-nullable, causing the error
• Added passive_deletes=True to User relationships (access_tokens, chats, role_assignments, organizations) so
  SQLAlchemy defers to the existing database-level ON DELETE CASCADE constraints instead of attempting to nullify the foreign
  keys

Summary by cubic

Set passive_deletes=True on User relationships (AccessToken, Chat, UserRoleAssignment, and Organization memberships) to rely on DB cascades during deletion and membership removal. Prevents foreign key violations and unnecessary ORM deletes when removing a user from an organization.

^{Written for commit 2ea1859. Summary will update on new commits.}