Improved consistency across OpenAI, Claude, and Gemini handlers by replacing initial `select` statement with a `for` loop for better readability and error-handling robustness.
Normalize action handling by accommodating wildcard patterns in route definitions for Gemini endpoints. Adjust `request.Action` parsing logic to correctly process routes with prefixed actions.
**feat(handlers, executor): add Gemini 3 Pro Preview support and refine Claude system instructions**
- Added support for the new "Gemini 3 Pro Preview" action in Gemini handlers, including detailed metadata and configuration.
- Removed redundant `cache_control` field from Claude system instructions for cleaner payload structure.
- Replaced `config.Config` with `config.SDKConfig` across components for simpler configuration management.
- Updated proxy setup functions and handlers to align with `SDKConfig` improvements.
- Reorganized handler imports to match new SDK structure.