Enhance PlannerAgent with entity recognition and coordination strategies - Implemented enhanced entity recognition and intent analysis in the PlannerAgent, allowing for improved query processing and coordination strategies. Updated the MusicRecommenderState model to include new fields for extracted entities, intent analysis, and conversation context. Enhanced logging and reasoning steps for better traceability during planning. Revised design documentation to reflect these changes and outline future enhancements.

Enhance design documentation for PlannerAgent entity recognition - Expanded the design document to detail current functionality, limitations, strengths, and proposed enhancements for the PlannerAgent. Included before and after examples of query processing to illustrate improvements in entity extraction and coordination strategies. Updated TODO list to reflect ongoing enhancements.

Update dependencies and enhance logging and configuration - Added google-generativeai to pyproject.toml and uv.lock, improved logging in main.py, and updated environment variable loading for better configuration management. Also, refined the .gitignore to include .gradio directory.