Split SimpleLogProcessor and BatchLogProcessor out of single file

[drewrelmas]

Fixes # N/A
Design discussion issue (if applicable) # N/A

Changes

Improve the readability of the codebase by splitting the LogProcessor trait and its implementations into separate files. Does not introduce breaking changes or alter usage of these components in examples.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

Attention: Patch coverage is 82.05446% with 145 lines in your changes missing coverage. Please review.

Project coverage is 79.1%. Comparing base (00ebc98) to head (4400ccf).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
opentelemetry-sdk/src/logs/batch_log_processor.rs	81.9%	100 Missing ⚠️
opentelemetry-sdk/src/logs/simple_log_processor.rs	82.2%	45 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #2661   +/-   ##
=====================================
  Coverage   79.1%   79.1%           
=====================================
  Files        120     122    +2     
  Lines      22562   22562           
=====================================
  Hits       17861   17861           
  Misses      4701    4701           

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[cijothomas]

Thanks! There are other places that could benefit from similar rearrangement, feel free to explore and make changes when you have bandwidth!

[lalitb]

thanks.