- Implement `/api/channel/models_enabled` endpoint to retrieve enabled models
- Add `EnabledListModels` handler in controller
- Create new `ModelRatioNotSetEditor` component for managing unset model ratios
- Update router to include new models_enabled route
- Add internationalization support for new model management UI
- Include GPT-4.5 preview model in OpenAI model list
- Support setting reasoning effort via model name suffix
- Add `-high`, `-medium`, and `-low` suffixes to control reasoning effort
- Update README with new model configuration option
- Modify OpenAI adaptor to handle reasoning effort settings
