fix: openai ConcatResponseMetaExtensions

[mrh997]

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 78.73%. Comparing base (d04d4b5) to head (17abeea).
⚠️ Report is 1 commits behind head on release/agentic_model.

Files with missing lines	Patch %	Lines
schema/openai/extension.go	0.00%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@                    Coverage Diff                    @@
##           release/agentic_model     #678      +/-   ##
=========================================================
- Coverage                  78.77%   78.73%   -0.05%     
=========================================================
  Files                        132      132              
  Lines                      13259    13256       -3     
=========================================================
- Hits                       10445    10437       -8     
- Misses                      1943     1945       +2     
- Partials                     871      874       +3     

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