Fix superadmin access control and modal aria-hidden warning

- Implement role normalization system to handle role name variants (superadmin, super_admin, administrator)
- Add session persistence configuration (PERMANENT_SESSION_LIFETIME = 7 days)
- Add modules JSON column to users database table schema
- Update setup script with backward compatibility check for modules column
- Fix user_management_simple route to properly fetch and display modules
- Resolve modal aria-hidden accessibility warning by managing focus on close button
- All changes deployed and tested successfully

py_app/instance/external_server.conf

@@ -1,4 +1,3 @@
-# Database Configuration - Generated on Fri Dec 26 17:40:32 EET 2025
 server_domain=db
 port=3306
 database_name=trasabilitate