perf(admin): implement server-side search and virtualization for tenant list

- Backend: Added 'search' parameter to TenantRepository and TenantService.
- Backend: Updated all Tenant list calls to support searching.
- Backend: Enhanced UserRepository.List to support cursor-based pagination and search.
- Frontend: Switched TenantListPage to use useInfiniteQuery for lazy loading.
- Frontend: Implemented list virtualization in TenantHierarchyView using @tanstack/react-virtual.
- Frontend: Added server-side search with debouncing (useDeferredValue).
- Fixed various Go compilation errors caused by method signature changes.

backend/internal/handler/hanmac_email_policy.go

@@ -113,7 +113,7 @@ func (h *UserHandler) resolveHanmacEmailScope(ctx context.Context) (*hanmacEmail
 		return nil, nil
 	}
 
-	tenants, _, err := h.TenantService.ListTenants(ctx, 10000, 0, "")
+	tenants, _, err := h.TenantService.ListTenants(ctx, 10000, 0, "", "")
 	if err != nil {
 		return nil, err
 	}