Refactor: UI Enhancements, Dependency Updates, and CI Fixes

[dmitrkozlovsk]

Key Changes:

• Material Design icons have been added to the navigation bar for better visual identification of sections (st.Page).
• Corrected the use of the deprecated use_container_width parameter in Streamlit components.
• The pydantic-ai version has been updated to ~=1.1.0. The codebase has been updated accordingly, replacing the Usage API with the new RunUsage.
• Implemented support for ThinkPart to provide a more detailed view of the AI's thinking process in the chat.
• Disabled anonymous telemetry in ChromaDB to align with privacy policies.
• Improved the initial setup script (make setup): it now checks for an existing expanto.db and avoids overwriting it. A force=true option has been added to allow for forced recreation of the database.

[dmitrkozlovsk]

closes #12