Fix artifact staging windows filename

[Abacn]

Please add a meaningful description for your change here

Fixes #39336

Port from #39363,

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[Abacn]

R: @Eliaaazzz since you reviewed #39363

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[codecov]

Codecov Report

❌ Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.34%. Comparing base (52d74b9) to head (3a7fd52).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...s/fnexecution/artifact/ArtifactStagingService.java	33.33%	1 Missing and 1 partial ⚠️
...unners/fnexecution/environment/ProcessManager.java	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #39916      +/-   ##
============================================
+ Coverage     55.06%   58.34%   +3.28%     
- Complexity     1722    13485   +11763     
============================================
  Files          1075     2568    +1493     
  Lines        171582   268734   +97152     
  Branches       1262    11029    +9767     
============================================
+ Hits          94474   156803   +62329     
- Misses        74838   105999   +31161     
- Partials       2270     5932    +3662     

Flag	Coverage Δ
java	64.46% <25.00%> (-3.23%)	⬇️

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[Eliaaazzz]

Thanks for the ping, Yi, and thanks for picking this up together with the Windows CI wiring. I checked out the head commit on Windows 11 (JDK 11) and ran the module tests locally.

What I verified locally:

• :runners:java-fn-execution:test passes at head, all 138 tests across 34 classes, including the new testStageArtifactsWithInvalidFilenameCharacters and the reworked ProcessManagerTest.
• The new test genuinely catches a regression on Windows: if I revert the sanitization, it fails with ExecutionException: StatusRuntimeException: UNKNOWN out of offer, and the server side logs InvalidPathException: Illegal char <:>. With the windows-latest leg now running this module in java_tests.yml, that failure would show up in CI.
• The environment sanitization resolves exactly the failure reported in #39336, and the env id in the new test matches the one from that report.

One substantive comment inline on createFilename, with a repro: the base component can still produce an invalid name for file-type artifacts.

On the two red checks:

• beam_PreCommit_Flink_Container timed out in the Java Combine step. The last logged Gradle task is :runners:flink:2.0:jar and no test execution output appears before the timeout, while :runners:java-fn-execution:jar had completed cleanly a few minutes earlier. Recent master runs of that workflow are green, and I could not find a patch-related failure in the log.
• codecov/patch flags three missing or partial lines, and they are the IS_OS_WINDOWS branches; the Java coverage upload runs on Ubuntu, which cannot take them.

Small question on java_tests.yml: the harness and runner steps used to carry if: always(), so they still ran when :sdks:java:core:test failed. Now an early failure skips them. Is that trade intentional, together with the single !success() upload?