perf(frontend): split admin bundles and tighten data fetching

Add next/dynamic lazy loading for database, logs, and settings heavy
modules; migrate access-logs and task-executions to React Query; parallelize
login auth-sources with public config; consolidate users table tooltips;
enable lazy image decoding; and replace barrel @/lib/services imports with
direct module paths.

frontend/components/common/user/file-manager.tsx

@@ -242,6 +242,8 @@ export function UserFileManager() {
                   <img
                     src={getFileUrl(file.id, "medium") ?? undefined}
                     alt={file.file_name}
+                    loading="lazy"
+                    decoding="async"
                     className="max-h-full max-w-full object-contain rounded-md shadow-xs transition-transform duration-350 group-hover:scale-103"
                     onError={(e) => {
                       ;(e.currentTarget as HTMLImageElement).style.display = "none"