Solution/role based app setting[WIP]

[KMerdan]

Summary

This PR introduces a new is_admin property in the Account model and the corresponding utility method is_admin_role in the TenantAccountRole class. Additionally, it updates the AppService logic to prevent non-admin users from modifying the enable_site property. These changes enhance access control and ensure only administrators can manage critical application settings.

Key Changes:

• Added is_admin property to the Account model to simplify admin checks.

• Added is_admin_role static method to TenantAccountRole to encapsulate role-specific logic.

• Updated AppService to include a check for current_user.is_admin before updating the enable_site property.

• Included commented-out alternative implementation for handling the enable_site property for potential future use.

  Fixes # (replace with the relevant issue number or remove if not applicable).