GH-1053: force target files to be writable when embedSourcesInClassOutputs is true

[hypnoce]

Fixes GH-1053.

[ascopes]

Thanks for raising a fix!

One small comment, hope that is okay!

I did wonder whether it is possible to make an integration test case for this as well by copying one of the existing ones and removing the write flags on Git. It might not be simple to do that for Windows though so not too worried if not.

[hypnoce]

@ascopes I remove the writable check and added an integration test that should work both on unix (linux, macos) and dos (windows).

[ascopes]

Thanks for updating, looks good to me.

Once the pipeline is green, I'll merge it and tag it so it is on Maven Central for you 👍

[codecov]

Codecov Report

❌ Patch coverage is 78.94737% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.37%. Comparing base (e48173e) to head (8ad0a71).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...thub/ascopes/protobufmavenplugin/fs/FileUtils.java	78.95%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1054      +/-   ##
==========================================
- Coverage   94.51%   94.37%   -0.14%     
==========================================
  Files          78       78              
  Lines        2056     2075      +19     
  Branches      132      134       +2     
==========================================
+ Hits         1943     1958      +15     
- Misses         79       83       +4     
  Partials       34       34              

Flag	Coverage Δ
maven-3.9.16-java-17-macos-26	92.29% <78.95%> (-0.12%)	⬇️
maven-3.9.16-java-17-ubuntu-24.04	93.26% <78.95%> (-0.13%)	⬇️
maven-3.9.16-java-17-ubuntu-24.04-arm	92.29% <78.95%> (-0.12%)	⬇️
maven-3.9.16-java-17-windows-2025	92.29% <78.95%> (-0.12%)	⬇️
maven-3.9.16-java-21-ubuntu-24.04	93.26% <78.95%> (-0.13%)	⬇️
maven-3.9.16-java-21-windows-11-arm	92.29% <78.95%> (-0.12%)	⬇️
maven-3.9.16-java-25-ubuntu-24.04	93.26% <78.95%> (-0.13%)	⬇️
maven-3.9.6-java-17-ubuntu-24.04	93.26% <78.95%> (-0.13%)	⬇️
maven-4.0.0-rc-5-java-17-ubuntu-24.04	93.26% <78.95%> (-0.13%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...thub/ascopes/protobufmavenplugin/fs/FileUtils.java	94.60% <78.95%> (-5.40%)	⬇️

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.