- Add Biome as formatter and linter (replaces Prettier)
- Configure Husky + lint-staged for pre-commit hooks
- Add VS Code settings for format on save
- Ignore components/ui/ (shadcn generated code)
- Remove semicolons, use 4-space indent
- Reformat all files to new style
- Add Zod schema validation for log-feedback and log-save endpoints
- Create singleton LangfuseClient to avoid per-request instantiation
- Simplify log-save to only flag trace (no XML content sent)
- Use generic error messages to prevent info leakage
- Update log-feedback API to find existing chat trace by sessionId and attach score to it
- Update log-save API to create span on existing chat trace instead of standalone trace
- Add thumbs up/down feedback buttons on assistant messages
- Add message regeneration and edit functionality
- Add save dialog with format selection (drawio, png, svg)
- Pass sessionId through components for Langfuse linking
- Add handleExportWithoutHistory function for fetching current diagram state without saving to history
- Update onFetchChart to accept saveToHistory parameter (defaults to true)
- edit_diagram tool now fetches with saveToHistory=false since it only needs the current state
- Only the initial form submission saves to history as intended
- Add save button in chat input area with download icon
- Create SaveDialog component for filename input
- Export current diagram as .drawio file format
- Support custom filename with default timestamp-based name
Closes#53
When sending a message, the history was being added twice because:
1. handleExport() triggers exportDiagram() which adds to history
2. AI responds and loadDiagram() is called, which internally triggers
another export event in DrawIO, adding a duplicate entry
Added expectHistoryExportRef flag to track user-initiated exports and
only add to history when the export was explicitly requested.
