Update RBAC ORM models + alembic migration for new unified enum

Update RBAC ORM models to use the new unified enum:

- rbac_models/permission/permission.py (scope_type, entity_type columns)

- rbac_models/association_scopes_entities.py (scope_type, entity_type columns)

- rbac_models/migration/ (types.py, enums.py, utils.py, vfolder.py, domain.py, user.py, project.py)

Write a new alembic migration to update DB column types accordingly.

Depends on: BA-4522

JIRA Issue: BA-4523