Feature Request: Support Browser-Based/ADC Authentication for Google Gemini

[giovannimnz]

Hello RooCode Team,

Currently, the Google Gemini provider requires a manually generated API key. It would be a great improvement for security and convenience if the extension could also support browser-based authentication using Application Default Credentials (ADC), similar to how the official "Google - Gemini" VS Code extension works.

Benefits:

Users wouldn't need to manage or expose API keys in their settings.

It's a more secure authentication method.

It aligns with the best practices recommended by Google for local development environments.

Thank you for considering this feature!