Cherry-picked from decolua/9router PR #183.
Note: open-sse changes included but need further review due to extensive modifications.
Co-authored-by: Cursor <cursoragent@cursor.com>
* feat: implement Project ID service to fetch and cache real Project IDs from Google Cloud Code API
* fix: implement caching and cleanup for Project ID retrieval
* feat: add project ID invalidation and refresh logic after token updates
* refactor: remove unnecessary format changes
* feat: add on-demand project ID retrieval for antigravity requests