refactor: migrate remaining components to Design System v4

111 files across 14 directories: common, tree-editor, kb-accelerator,
copilot, assistant, analytics, library, procedural, procedural-editor,
public, script-editor, ui, admin, step-library.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/components/common/StarRating.tsx

@@ -48,14 +48,14 @@ export function StarRating({
               sizeClasses[size],
               star <= value
                 ? 'fill-yellow-400 text-yellow-400'
-                : 'fill-none text-muted-foreground',
+                : 'fill-none text-[#848b9b]',
               !readonly && 'hover:text-yellow-300'
             )}
           />
         </button>
       ))}
       {showCount && (
-        <span className="ml-1 text-sm text-muted-foreground">
+        <span className="ml-1 text-sm text-[#848b9b]">
           ({value}/5)
         </span>
       )}