Documents the complete ACE → CodeMirror migration, including:
- Root cause analysis of react-ace CJS/ESM incompatibility with Vite
- Migration steps and rationale for @uiw/react-codemirror
- Flex layout height constraint fix and the underlying pattern
- Key technical learnings about CJS/ESM interop and flex layouts
- Remaining steps and continuation prompt for next session
This serves as the authoritative reference for why we use CodeMirror
and how to properly constrain third-party components in flex layouts.
