Force clear current session key on init

feat: Display new session in tabs immediately

Enhance session loading and error handling

feat: Implement local session fallback for new sessions

feat: Generate default session name for new sessions

Add debug logs for session management initialization

Refactor: Streamline session initialization flow

Refine login success and enhance session creation logging

Refactor session tab management to separate rendering and reduce fetches

Based on the provided git diff, here's a concise and descriptive commit message:

Ensure current session history is loaded during initialization

Add session history API and auto-init session management

Refactor: Move session tab bar structure to HTML

Modularize frontend CSS and JavaScript assets