Fix Monaco workspace initialization and selected-file preview regressions in WorkspaceCodeEditor

[rushabhcodes]

Summary

This PR fixes two regressions in the workspace editing and preview flow:

1. WorkspaceCodeEditor could remain stuck on Loading editor... even after the priority file was fetched.
2. The runframe preview could switch to non-runnable helper files when the selected file was not a real entrypoint.

It also strengthens Monaco workspace model initialization so cross-file TypeScript state is synchronized before the editor is shown.

What Changed

• Added explicit workspace model readiness tracking in WorkspaceCodeEditor.
• Switched initial workspace model sync to useLayoutEffect so Monaco models are populated before the editor renders.
• Added a post-mount re-sync to trigger a clean TypeScript pass once the editor is mounted.
• Fixed the isPriorityFileFetched compatibility gate so true means the priority file is ready instead of blocking editor mount.
• Tightened tscircuit entrypoint resolution so selected files only override the preview when they look like a real default-exported entry component.
• Prevented named-export helper files from hijacking the live preview.
• Updated Monaco workspace URIs to use monaco.Uri.file(...) for file-backed workspace models.
• Expanded the runframe fixture to exercise a multi-file board setup with imported components and manual edits.

User Impact

Before this change:

• Some hosts could leave the editor permanently stuck in a loading state.
• Monaco could initialize before the full workspace model graph was ready.
• Selecting a helper TSX file could redirect the preview away from the actual runnable board entrypoint.

After this change:

• The editor mounts once the workspace and priority file are actually ready.
• Cross-file Monaco state is synchronized earlier and refreshed after mount.
• The preview stays on a runnable board entrypoint unless the selected file is a valid default-exported entry file.

Why This Matters

This is a user-facing workspace UX fix. It improves editor readiness, stabilizes cross-file Monaco behavior, and prevents incorrect preview switching during normal file navigation in multi-file tscircuit projects.

Validation

• bun run typecheck

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
monaco-code-editor	Ready	Preview, Comment	Jun 29, 2026 3:12am

[tscircuitbot]

---

Thank you for your contribution! 🎉

PR Rating: ⭐⭐⭐
Impact: Major

Track your contributions and see the leaderboard at: tscircuit Contribution Tracker

---