[release/11.0.1xx] Honor MTP zero-tests and exit-code policies in dotnet test

[Evangelink]

Summary

Backport the MTP zero-tests and exit-code policy fixes from 6eb73fc and the validated follow-up e08c3f4 to release/11.0.1xx.

• fixes the aggregate all-skipped/zero-tests result
• reconstructs policies from explicit and default .testconfig.json files
• preserves environment > CLI > JSON precedence for ignored exit codes
• matches environment variable names case-insensitively on Windows and case-sensitively on Unix
• adds the end-to-end regressions and supporting parser/queue/reporter tests

The cherry-pick conflicts were limited to MicrosoftTestingPlatformTestCommand.cs and TestCommandParserTests.cs; the resolutions preserve release-only retry and output behavior without importing unrelated main-only changes.

References #56219 and #56296.

Validation

• build.cmd
• focused dotnet.Tests: 67 passed, 0 failed, 1 platform-specific skip (68 total)

.\.dotnet\dotnet.exe .github\skills\targeted-test\scripts\RunTargetedTests.cs -- --project test\dotnet.Tests\dotnet.Tests.csproj --filter "FullyQualifiedName~TestCommandParserTests|FullyQualifiedName~TestApplicationActionQueueTests|FullyQualifiedName~TerminalTestReporterTests|Name~RunAllSkippedTestsHonors|Name=RunNoTestsHonorsIgnoredExitCodeFromExplicitConfigurationFile|Name=RunMinimumExpectedTestsViolationHonorsIgnoreExitCodePolicy"

[azure-pipelines]

Azure Pipelines:
Successfully started running 1 pipeline(s).
2 pipeline(s) were filtered out due to trigger conditions.
There may be pipelines that require an authorized user to comment /azp run to run.

[Copilot]

Copilot review overview

🟡 Changes recommended

Seven moderate findings remain unresolved across policy reconstruction, cancellation reporting, and Unix-specific regression coverage.

Get a fresh assessment by requesting another Copilot review.

Review tier: Lite
Findings: 1

Open (1)

• Cover Unix-sensitive environment variable matching · New

What changed in this PR

Backports MTP zero-test and ignored-exit-code policy handling to dotnet test for the release/11.0.1xx branch.

Changes:

• Reconstructs policies from CLI arguments, response/configuration files, and environment variables.
• Applies policies to aggregate exit codes and terminal summaries.
• Adds parser, queue, reporter, and end-to-end regression tests.

File	Review notes
test/​dotnet.Tests/​CommandTests/​Test/​TestCommandParserTests.cs	No final findings.
test/​dotnet.Tests/​CommandTests/​Test/​TestApplicationActionQueueTests.cs	No final findings.
test/​dotnet.Tests/​CommandTests/​Test/​TerminalTestReporterTests.cs	No final findings.
test/​dotnet.Tests/​CommandTests/​Test/​GivenDotnetTestBuildsAndRunsTests.cs	Moderate (1 vote): add Unix case-sensitive coverage for the lowercase launch-profile environment variable.
src/​Cli/​dotnet/​Commands/​Test/​MTP/​TestApplicationActionQueue.cs	No final findings.
src/​Cli/​dotnet/​Commands/​Test/​MTP/​Terminal/​TerminalTestReporter.cs	Moderate (1 vote): preserve cancellation in the failure decision so cancelled runs are reported as aborted.
src/​Cli/​dotnet/​Commands/​Test/​MTP/​Options.cs	No final findings.
src/​Cli/​dotnet/​Commands/​Test/​MTP/​MicrosoftTestingPlatformTestCommand.cs	Moderate findings: validate repeated policy options consistently (1 vote); guard config-path normalization (1 vote); guard response-file path normalization (1 vote); add Unix case-sensitive coverage (2 votes); distinguish a missing config value from an absent option (1 vote).