docs(antigravity): 📚 document quota tracking, background jobs, and error handling

docs(antigravity): 📚 update documentation for credential prioritization and model support changes

docs: 📚 add comprehensive documentation for new features and providers

docs(readme): 📚 documentation expansion to cover new PR features(and in general)

feat(core): introduce model whitelisting to override blacklists

docs: update project descriptions and component names

feat(core): implement deadline-driven request execution and resilient error handling

docs(rotator_library): Load API keys dynamically from environment variables

docs: Big documentation update part

feat: Update documentation and example configurations for improved clarity and usability

feat: Add OpenRouter and Chutes.ai provider support

feat: Implement per-model API key cooldowns

feat: Add detailed documentation and installation instructions for the rotating API key client

feat: Refactor project into reusable API key rotation library and proxy