regenerateResponse removed the previous answer before checking for a model and then returned silently, leaving the conversation without a reply. It now checks first and explains that a model is required, like sendMessage. The duplicated streaming code in sendMessage and regenerateResponse is now a single streamAnswer helper.
The edit path duplicated the streaming flow with inline require() calls; it now reuses regenerateResponse, which also fixes:
- edited conversations were never saved to History
- the answer generated after an edit could not be stopped (no abort handle kept)
Stopping a stream now saves the partial conversation, like finishing or failing does.
Adds characterization tests for ChatScreen and useLMStudio.
evandro