fix: responses schema normalization

[woorui]

No description provided.

[gemini-code-assist]

Code Review

This pull request introduces response streaming checks based on success status codes and adds a request body sanitization mechanism for specific GPT-5.6 models to normalize message-like inputs by ensuring they have a type field set to 'message'. The review feedback correctly points out that the current sanitization logic discards extra fields (such as id, phase, or tool-related fields) by rebuilding the message map from scratch. It is recommended to mutate the existing JSON object in-place to preserve these fields, and to update the test assertions accordingly.

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[codecov]

Codecov Report

❌ Patch coverage is 96.99248% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 60.75%. Comparing base (63c7020) to head (8887eac).

Files with missing lines	Patch %	Lines
src/model_api_provider/providers/responses.rs	96.99%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1255      +/-   ##
==========================================
+ Coverage   60.29%   60.75%   +0.46%     
==========================================
  Files          46       46              
  Lines       10476    10609     +133     
==========================================
+ Hits         6316     6445     +129     
- Misses       4160     4164       +4     

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