[WIP] Portable VoidCoder

[ganesh-skumar]

Makes Java VoidCoder portable, to handle void values across SDKs

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[gemini-code-assist]

Summary of Changes

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This pull request introduces support for a portable VoidCoder in the Apache Beam pipeline model. By defining a standard URN for the Void type and registering it within the Java SDK's model coder infrastructure, this change ensures that void values can be consistently handled and serialized across different SDKs.

Highlights

• Protocol Buffer Update: Added the VOID coder definition to the StandardCoders enum in the pipeline runner API.
• Java SDK Integration: Registered VoidCoder in ModelCoderRegistrar and ModelCoders to enable its use across SDKs.
• Testing: Updated CoderTranslationTest to include VoidCoder in the known coders validation suite.

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[gemini-code-assist]

Code Review

This pull request introduces support for a standard VoidCoder in the Apache Beam runner API and Java SDK. It adds the VOID coder definition to the standard coders protobuf, registers VoidCoder in ModelCoderRegistrar and ModelCoders, and includes corresponding test coverage in CoderTranslationTest. There are no review comments, so no additional feedback is provided.

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[ganesh-skumar]

R: @robertwb

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.64%. Comparing base (b3a62ee) to head (0989197).

Additional details and impacted files

@@              Coverage Diff              @@
##             master   #38937       +/-   ##
=============================================
- Coverage     59.59%   56.64%    -2.95%     
+ Complexity    18374     3638    -14736     
=============================================
  Files          3061     1184     -1877     
  Lines        301089   188015   -113074     
  Branches      15727     3753    -11974     
=============================================
- Hits         179432   106508    -72924     
+ Misses       113785    78040    -35745     
+ Partials       7872     3467     -4405     

Flag	Coverage Δ
java	72.65% <ø> (+6.42%)	⬆️

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