Reason: Request Failed: 400 {"type":"error","error":

### Describe the bug

Sorry, your request failed. Please try again.

Client Request Id: 37d002d9-1b1a-4391-87c7-c5e78738a4d6

GH Request Id: C773:3572CB:8F80BEE:9D6A6D9:6A5F0843

Reason: Request Failed: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.1.content.1: thinking or redacted_thinking blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response."},"request_id":"req_011CdEgFCtmuNZwA4j7YktHw"}

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

报告没有提及任何文件、测试或入口点，也没有提供复现步骤。首先使用提供的客户端和 GitHub request IDs 重现失败的请求，然后跟踪构造 assistant message 的请求处理路径；完成的标准是识别并阻止无效请求，并提供一个回归测试。

由索引模型根据 Issue 内容生成。