Add ESC fallback actions, improve empty LLM reply handling, and provide ChromaDB backup scripts
- Implemented additional ESC key actions to help close unexpected homepage advertisements that previously could not be dismissed.
- Improved canned response handling when LLM returns empty or null replies, ensuring smoother conversational flow.
- Added optional utility scripts for backing up and restoring ChromaDB memory storage.
- These changes aim to enhance system robustness, reduce interruption from UI anomalies, and provide better data management options.
