MLC-318/integrate agent CRUD and agency fetch and type updates

Integrated full CRUD operations for agents:

Create / Update agent info Update agent status Delete agent with confirmation toast and UI refresh

Enhanced search filters with agency name support Improved error handling and toast notifications Updated frontend types (IAgent, IUser) to reflect backend changes (e.g., agencyId as Long) Minor adjustments in client components to align with updated shared models and APIs Fixed table rendering and agent quick view details