refactor(studio): update layout, config, and remove agent activity tracking (#64)

## Summary
- **NLELayout**: Add toolbar slot, composition breadcrumb navigation, improved responsive layout
- **Vite config**: Add full project API (preview, thumbnail, render, file CRUD) for standalone dev mode
- Remove AgentActivityTrack component (replaced by timeline clips)
- Add HTML editor utilities for composition source editing
- Guard setInterval cleanup to dev-only to prevent `vite build` from hanging in CI

🤖 Generated with [Claude Code](https://claude.com/claude-code)

packages/studio/src/components/editor/SourceEditor.tsx

@@ -26,7 +26,9 @@ function getLanguageExtension(language: string) {
     case "js":
     case "typescript":
     case "ts":
-      return javascript({ typescript: language === "typescript" || language === "ts" });
+      return javascript({
+        typescript: language === "typescript" || language === "ts",
+      });
     default:
       return html();
   }