phsl / new-api

- Introduced `isNoThinkingRequest` and `trimModelThinking` functions to manage model names and thinking configurations.
- Updated `GeminiHelper` to conditionally adjust the model name based on the thinking budget and request settings.
- Refactored `ThinkingAdaptor` to streamline the integration of thinking capabilities into Gemini requests.
- Cleaned up commented-out code in `FetchUpstreamModels` for clarity.

These changes improve the handling of model configurations and enhance the adaptability of the Gemini relay system.