CI build intermittently fails on Windows with file locks in `obj\Release\*\*.GeneratedMSBuildEditorConfig.editorconfig` and `CS2012`

[jeffpatton1971]

Summary
On windows-latest, dotnet build intermittently fails with file locking errors in src\Xml2Doc.Core\obj\Release\{tfm}\...GeneratedMSBuildEditorConfig.editorconfig and/or CS2012 failing to write obj\Release\{tfm}\Xml2Doc.Core.dll.

Environment

• Runner: windows-latest
• Build command: dotnet build ... --configuration Release --no-restore
• Observed SDK: 10.0.100 (from build output)

Steps to Reproduce

1. Run Merge Test Workflow on a PR targeting main.
2. dotnet clean
3. dotnet restore
4. dotnet build ... --configuration Release --no-restore

Expected
Build completes successfully.

Actual
Build fails with errors like:

• Microsoft.Managed.Core.targets(...): The process cannot access ...GeneratedMSBuildEditorConfig.editorconfig because it is being used by another process.
• CSC : error CS2012: Cannot open ...obj\Release\net9.0\Xml2Doc.Core.dll for writing -- The process cannot access the file because it is being used by another process. ([Microsoft Learn][2])

Notes / suspected cause
This appears to be a Windows file-handle contention issue involving Roslyn/MSBuild intermediates and/or compiler/build servers, exacerbated by parallel build behavior.

Proposed fix

• Disable/flush build servers in CI (dotnet build-server shutdown, --disable-build-servers). ([Microsoft Learn][3])
• Reduce parallelism for the CI build (-m:1, MSBUILDDISABLENODEREUSE=1). ([GitHub][4])
• Optionally disable shared compilation in CI (UseSharedCompilation=false) since it defaults to true. ([GitHub][1])

Acceptance criteria

• CI build and tests pass reliably across repeated runs on windows-latest.
• No intermittent “file used by another process” failures.