Remove OS-Specific Builds

[benrr101]

Description:
This PR is one of a few to finish removing OS-specific-ness in the project. In this step:

• Removed OS-specific build targets from build.proj (moved to BuildSqlClientImpl to differentiate from ref and notimplemented targets)
• Removed TargetOs stuff from csproj files, and added net462 to all build targets (Copilot thinks this doesn't work, but it clearly does)
• Removed OS folder from output path of projects
• Updated nuspec for MDS to use OS-agnostic assemblies for both windows and unix runtime
  • This is admittedly hacky, but enables in-place change without dramatic deletion of projects. The not-supported project will be deleted in the next step, which will allow the OS-agnostic assemblies to be used directly as the lib assemblies
• Removed OS-specific behavior from perf test project 🤖

Testing:

• ✅ build.proj targets work on windows and linux
• ✅ sqlclient-pr is passing
• ✅ old PR pipelines are passing
• ✅ sqlclient-ci pipeline
  https://sqlclientdrivers.visualstudio.com/public/_build/results?buildId=166024&view=results
• ✅ sqlclient-ci-package pipeline
  https://sqlclientdrivers.visualstudio.com/public/_build/results?buildId=167254&view=results
• ✅ non-official pipeline
  https://dev.azure.com/SqlClientDrivers/ADO.Net/_build/results?buildId=166026&view=results

[Copilot]

Pull request overview

This draft PR removes the OS-specific build dimension (Unix vs Windows) from SqlClient’s build and test infrastructure, while preserving the existing NuGet package layout via a temporary “same binaries for all OSes” approach.

Changes:

• Consolidates build.proj and Kerberos CI steps to use a single BuildSqlClient target instead of per-OS build targets.
• Updates SqlClient output and packing layout (notably Microsoft.Data.SqlClient.csproj OutputPath and Microsoft.Data.SqlClient.nuspec) to no longer include OS-qualified artifact folders.
• Simplifies test/perf tooling by removing OS-conditional compilation in some test tools and dropping Windows-only BenchmarkDotNet diagnoser support.

Reviewed changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 13 comments.

Show a summary per file

File	Description
src/Microsoft.Data.SqlClient/tests/UnitTests/Microsoft.Data.SqlClient.UnitTests.csproj	Removes TargetOs-based multi-targeting logic; updates Package-mode runtime assembly HintPath logic.
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/TDS.EndPoint.csproj	Removes explicit Compile item lists and OS-conditional source inclusion.
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/SSPI/SSPIContext.Unix.cs	Deletes the Unix SSPI stub implementation.
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/SSPI/SSPIContext.cs	Adds runtime OS checks to enforce Windows-only SSPI execution.
src/Microsoft.Data.SqlClient/tests/TestUdts/Utf8String/Utf8String.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/TestUdts/Shapes/Shapes.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/TestUdts/Circle/Circle.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/TestUdts/Address/Address.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/StressTests/Directory.Build.props	Removes TargetOs-based targeting logic for stress test builds.
src/Microsoft.Data.SqlClient/tests/PerformanceTests/runnerconfig.jsonc	Removes configuration entries tied to Windows-only diagnosers.
src/Microsoft.Data.SqlClient/tests/PerformanceTests/Program.cs	Removes propagation of Windows-only diagnoser config into BenchmarkConfig.
src/Microsoft.Data.SqlClient/tests/PerformanceTests/Microsoft.Data.SqlClient.PerformanceTests.csproj	Removes Windows-only BenchmarkDotNet.Diagnostics.Windows dependency and WINDOWS constant.
src/Microsoft.Data.SqlClient/tests/PerformanceTests/Config/Config.cs	Removes the Windows-only profiler flag from the config model.
src/Microsoft.Data.SqlClient/tests/PerformanceTests/Config/BenchmarkConfig.cs	Removes conditional Windows diagnoser wiring.
src/Microsoft.Data.SqlClient/tests/ManualTests/Microsoft.Data.SqlClient.ManualTests.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/FunctionalTests/Microsoft.Data.SqlClient.FunctionalTests.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/CustomConfigurableRetryLogic/CustomRetryLogicProvider.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/tests/Common/Microsoft.Data.SqlClient.TestCommon.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
src/Microsoft.Data.SqlClient/src/Microsoft.Data.SqlClient.nuspec	Updates packed artifact paths to match non-OS-qualified build outputs while keeping runtime folder structure.
src/Microsoft.Data.SqlClient/src/Microsoft.Data.SqlClient.csproj	Removes TargetOs/NormalizedTargetOs usage; updates TargetFrameworks and OutputPath accordingly.
src/Microsoft.Data.SqlClient.Extensions/Azure/test/Azure.Test.csproj	Removes TargetOs-based targeting logic; now multi-targets directly.
eng/pipelines/ci/kerberos/sqlclient-ci-kerberos-pipeline.yml	Stops passing OS-specific build targets into the shared Kerberos build step template.
eng/pipelines/ci/kerberos/build-and-test-steps.yml	Removes buildTarget parameter and builds via -t:BuildSqlClient.
build.proj	Removes per-OS SqlClient build/test targets and replaces with a unified implementation build target.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 64.02%. Comparing base (9b20e5e) to head (579854d).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4474      +/-   ##
==========================================
- Coverage   64.73%   64.02%   -0.72%     
==========================================
  Files         288      288              
  Lines       44088    70331   +26243     
==========================================
+ Hits        28542    45026   +16484     
- Misses      15546    25305    +9759     

Flag	Coverage Δ
CI-SqlClient	64.69% <ø> (-0.05%)	⬇️
PR-SqlClient-Project	63.65% <ø> (?)

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[Copilot]

Pull request overview

Copilot reviewed 24 out of 24 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (2)

src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/SSPI/SSPIContext.cs:142

• CreateServer calls ThrowIfNotWindows(), but the SSPIContext constructor also calls it. This results in a redundant OS check (and double work) on the Windows path.

This issue also appears on line 163 of the same file.
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/SSPI/SSPIContext.cs:168

• CreateClient calls ThrowIfNotWindows(), but the SSPIContext constructor also calls it. This results in a redundant OS check (and double work) on the Windows path.

[edwardneal]

This all looks good. A few notes from my earlier explorations in the area:

• The notsupported version of the netstandard2.0 ref assemblies is copied to lib/netstandard2.0. I'm not sure whether it can be safely replaced with the ref assembly - or for that matter, whether it's necessary at all. Once it's been replaced though, the tools/GenAPI directory can be deleted.
• There are a number of issues which the restructured package should be tested against. I expect that all of them will be fixed by the restructuring:
  • Does it make sense to package the net46 Microsoft.Data.SqlClient.dll inside both the lib and runtimes directories? #903
  • Microsoft.Data.SqlClient is not supported on this platform with .NET9 class library and winforms app #3006
  • Issue using Microsoft.Data.SqlClient with PowerShell 7.5.2 #3577
  • dotnet publish -r linux-x64 resolves reference assembly instead of runtime assembly for net10.0 apps #4461
• Besides the above, these issues might need to be re-reviewed:
  • .NET Standard library not working with .NET Framework #2786
  • Raise exception on calling SqlClientFactory.Instance from facade assembly #4081

[benrr101]

Thanks for the notes - I've got a couple responses inline

This all looks good. A few notes from my earlier explorations in the area:

* The notsupported version of the netstandard2.0 ref assemblies is copied to `lib/netstandard2.0`. I'm not sure whether it can be safely replaced with the ref assembly - or for that matter, whether it's necessary at all. Once it's been replaced though, the `tools/GenAPI` directory can be deleted.

Yep, that's the next hurdle I have to tackle. It may be a showstopper for continuing past this PR as the alternatives might be too much effort for the simplification of the projects. I have an idea I want to try before I give up, though.

* There are a number of issues which the restructured package should be tested against. I expect that all of them will be fixed by the restructuring:
  
  * [Does it make sense to package the net46 Microsoft.Data.SqlClient.dll inside both the lib and runtimes directories? #903](https://github.com/dotnet/SqlClient/issues/903)
  * [Microsoft.Data.SqlClient is not supported on this platform with .NET9 class library and winforms app #3006](https://github.com/dotnet/SqlClient/issues/3006)
  * [Issue using Microsoft.Data.SqlClient with PowerShell 7.5.2 #3577](https://github.com/dotnet/SqlClient/issues/3577)
  * [dotnet publish -r linux-x64 resolves reference assembly instead of runtime assembly for net10.0 apps #4461](https://github.com/dotnet/SqlClient/issues/4461)

* Besides the above, these issues might need to be re-reviewed:
  
  * [.NET Standard library not working with .NET Framework #2786](https://github.com/dotnet/SqlClient/issues/2786)
  * [Raise exception on calling `SqlClientFactory.Instance` from facade assembly #4081](https://github.com/dotnet/SqlClient/issues/4081)

Those are all good suggestions. I'll check against those before I report this as ready to go.f

[Copilot]

Pull request overview

Copilot reviewed 20 out of 22 changed files in this pull request and generated no new comments.

[cheenamalhotra]

LGTM!

[mdaigle]

🥳

Only one spot stood out to me, otherwise looks good!

Do you anticipate this change to be visible to customers at all? Is there any case where someone might be dependent on having platform in the path in the nuget package?

[mdaigle]

does this work when running on unix? I wouldn't expect to see platform in any paths.