Update vote processing to default HF_REVISION to 'staging'

Enhance vote validation by incorporating Authorization header for hf_token and updating validate_vote_payload function to accept it as an argument.

Automated update of metadata.json with votes.json

Enhance vote processing by adding client IP tracking and duplicate vote prevention.

Refactor voting logic: Removed global votes handling from the commit_vote_updates and process_vote functions.

Add voting functionality to app.py: Implemented a new route to handle user votes via a POST request, including JSON validation and error handling. Updated config.py to include paths for votes, and enhanced hf_repo.py with functions to commit vote updates. Modified webhooks.py to create missing votes files during indexation.