feat: refactor clinic management into a dedicated settings tab

- Removed MyClinicPage and redirected its functionality to a new ClinicDoctorsPage.
- Created ClinicDoctorsManager component for managing doctors and invitations within the settings layout.
- Updated backend permissions to allow clinic owners to detach doctors, alongside admins.
- Adjusted API documentation to reflect new permission structure.
- Updated tests to cover new functionality and permissions.
- Modified sidebar and settings menu to reflect the new structure and role-based visibility.

assets/admin/pages/SettingsMenuPage.test.tsx

@@ -16,7 +16,7 @@ describe('SettingsMenuPage', () => {
       expect(screen.getByText(item.label)).toBeInTheDocument();
     }
     // clinic-only section is not shown to a doctor
-    expect(screen.queryByText('مدیریت مطب')).not.toBeInTheDocument();
+    expect(screen.queryByText('پزشکان کلینیک')).not.toBeInTheDocument();
   });
 
   it('links every section to its route', () => {