Add direct path code path

[m-trieu]

Add direct path code path

we will be able to run direct path pipelines by passing in the option is IsWindmillServiceDirectPathEnabled

• I added some new components (they are just encapsulated existing logic from StreamingDataflowWorker.java) and will back port this to StreamingDataflowWorker in a seperate pr
• the pr that added the channel caches were rolled back, am working on reintegrating that

R: @scwhittle

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[github-actions[bot]]

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[m-trieu]

@scwhittle still wrapping up the unit tests, just would like an initial pass thanks!

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R: @Abacn added as fallback since no labels match configuration

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 71.27%. Comparing base (96dc16a) to head (ec12c72). Report is 234 commits behind head on master.

:exclamation: Current head ec12c72 differs from pull request most recent head e60cb1e. Consider uploading reports for the commit e60cb1e to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #30764      +/-   ##
============================================
+ Coverage     70.95%   71.27%   +0.32%     
+ Complexity     4470     1485    -2985     
============================================
  Files          1257      904     -353     
  Lines        140917   112898   -28019     
  Branches       4305     1076    -3229     
============================================
- Hits          99989    80471   -19518     
+ Misses        37451    30408    -7043     
+ Partials       3477     2019    -1458     

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[github-actions[bot]]

Reminder, please take a look at this pr: @Abacn

[scwhittle]

@Abacn not sure how to turn off the reminders but this doesn't require a look. It is being broken apart into smaller PRs which I am reviewing.

[scwhittle]

@m-trieu Should we close this one for now? We can reopen after rebasing on top of the broken off PRs

[github-actions[bot]]

Reminder, please take a look at this pr: @Abacn