feat: DIA-2148: write exports using thread pool

[pakelley]

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Optimize export job by threading writes to storage

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[sentry]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: label_studio/io_storages/base_models.py

Function	Unhandled Issue
save_all_annotations	S3StorageError: Debugging info is not available for s3 endpoints on domain: . Please contact your Label Studio devops team if you require detailed error reporting for this domain. ... Event Count: 39

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[codecov]

Codecov Report

Attention: Patch coverage is 95.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 77.26%. Comparing base (8714cb3) to head (70ff4cc).
Report is 16 commits behind head on develop.

Files with missing lines	Patch %	Lines
label_studio/io_storages/base_models.py	95.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #7342      +/-   ##
===========================================
- Coverage    77.27%   77.26%   -0.01%     
===========================================
  Files          190      190              
  Lines        14682    14697      +15     
===========================================
+ Hits         11345    11356      +11     
- Misses        3337     3341       +4     

Flag	Coverage Δ
pytests	77.26% <95.00%> (-0.01%)	⬇️

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[pakelley]

/fm sync

Workflow run