Qwen3.5 reasoning content display

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### 1. Is this request related to a challenge you're experiencing? Tell me about your story.

When deploying Qwen3.5 using the vllm method and integrating it with Dify, the thinking mode is enabled by default, but the content of the thinking process cannot be displayed.

### 2. Additional context or comments

When deploying Qwen3.5 using the vllm method and integrating it with Dify, the thinking mode is enabled by default, but the content of the thinking process cannot be displayed.

### 3. Can you help us with this feature?

- [x] I am interested in contributing to this feature.