[fix][evaluation]expt download

[tpfz]

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[CozeLoop]

Submitted inline review comments addressing secure logging of signed URLs.

[codecov]

Codecov Report

❌ Patch coverage is 89.47368% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...ules/evaluation/domain/service/expt_export_impl.go	33.33%	2 Missing ⚠️

@@            Coverage Diff             @@
##             main     #325      +/-   ##
==========================================
+ Coverage   69.46%   69.49%   +0.02%     
==========================================
  Files         588      589       +1     
  Lines       55147    55156       +9     
==========================================
+ Hits        38310    38328      +18     
+ Misses      13938    13930       -8     
+ Partials     2899     2898       -1     

Flag	Coverage Δ
unittests	69.49% <89.47%> (+0.02%)	⬆️

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Files with missing lines	Coverage Δ
...application/convertor/target/eval_target_record.go	86.95% <100.00%> (ø)
...es/evaluation/domain/service/url_processor_impl.go	100.00% <100.00%> (ø)
...ules/evaluation/domain/service/expt_export_impl.go	77.72% <33.33%> (+1.35%)	⬆️

... and 1 file with indirect coverage changes

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