feat: Phase 5.5 wire meta-package to ship the analyzer as a dev-only NuGet

Pipeline/Build.Pack.cs

@@ -5,7 +5,9 @@
 using Nuke.Common;
 using Nuke.Common.IO;
 using Nuke.Common.ProjectModel;
+using Nuke.Common.Tools.DotNet;
 using Nuke.Common.Utilities.Collections;
+using static Nuke.Common.Tools.DotNet.DotNetTasks;
 using static Serilog.Log;
 
 // ReSharper disable AllUnderscoreLocalParameterName
@@ -59,6 +61,28 @@ partial class Build
 			AbsolutePath packagesDirectory = ArtifactsDirectory / "Packages";
 			packagesDirectory.CreateOrCleanDirectory();
 
+			// Pack the meta-package separately from the slnx build. The meta-package
+			// csproj disables GeneratePackageOnBuild because adding ProjectReferences
+			// to the analyzer projects from the meta-package was found to create a
+			// duplicate MSBuild graph node for those analyzers under parallel CI
+			// builds, racing on bin/.../deps.json files and failing GenerateDepsFile
+			// with "file in use". Packing here with NoBuild after Compile sidesteps
+			// the race entirely: the slnx build has already produced every analyzer
+			// DLL the meta-package needs to bundle into analyzers/dotnet/cs/. Pack
+			// runs against the .slnx (not the csproj) so $(SolutionDir) resolves for
+			// the README pack target; only the meta-package is IsPackable=true so it
+			// is the only project actually packed.
+			DotNetPack(s => s
+				.SetProject(Solution.Path)
+				.SetConfiguration(Configuration)
+				.EnableNoLogo()
+				.EnableNoRestore()
+				.EnableNoBuild()
+				.SetVersion(MainVersion.FileVersion + MainVersion.PreRelease)
+				.SetAssemblyVersion(MainVersion.FileVersion)
+				.SetFileVersion(MainVersion.FileVersion)
+				.SetInformationalVersion(MainVersion.InformationalVersion));
+
 			List<string> packages = new();
 			foreach (Project project in new[]
 			         {

Source/Testably.Abstractions.Migration/Testably.Abstractions.Migration.csproj

@@ -2,6 +2,44 @@
 
 	<PropertyGroup>
 		<RootNamespace>Testably.Abstractions.Migration</RootNamespace>
+		<!--
+			This is a one-shot dev tool: install, run the migration, uninstall.
+			DevelopmentDependency=true marks the package as dev-only so it does not
+			propagate to the consumer's transitive dependencies and is auto-treated
+			with PrivateAssets=all. Consumers must reference Testably.Abstractions.Testing
+			themselves so the dependency survives the migration package's removal.
+		-->
+		<DevelopmentDependency>true</DevelopmentDependency>
+		<!--
+			Pack runs separately from build (see Pipeline/Build.Pack.cs). Adding
+			ProjectReference items to the analyzer projects from here was found to
+			create a duplicate MSBuild graph node for those analyzers under parallel
+			CI builds, racing on bin/.../deps.json files and failing GenerateDepsFile
+			with "file in use". Disabling pack-on-build and packing separately with
+			NoBuild after the slnx is fully built sidesteps the race entirely. This
+			project must therefore always be built / packed via the .slnx, not as a
+			standalone csproj.
+		-->
+		<GeneratePackageOnBuild>false</GeneratePackageOnBuild>
 	</PropertyGroup>
 
+	<ItemGroup>
+		<!--
+			Pack the analyzer + codefix DLLs from their sibling projects' bin output.
+			Those projects are built by the slnx via the test / playground project
+			references; by the time Pack runs (after Compile in the Nuke pipeline) the
+			DLLs are guaranteed to exist. Paths use $(TargetFramework) and $(Configuration)
+			to track the central settings; PackagePath uses a trailing slash to match
+			sibling Pack metadata in the codebase.
+		-->
+		<None Include="..\Testably.Abstractions.Migration.Analyzers\bin\$(Configuration)\$(TargetFramework)\Testably.Abstractions.Migration.Analyzers.dll"
+			  Pack="true"
+			  PackagePath="analyzers/dotnet/cs/"
+			  Visible="false"/>
+		<None Include="..\Testably.Abstractions.Migration.Analyzers.CodeFixers\bin\$(Configuration)\$(TargetFramework)\Testably.Abstractions.Migration.Analyzers.CodeFixers.dll"
+			  Pack="true"
+			  PackagePath="analyzers/dotnet/cs/"
+			  Visible="false"/>
+	</ItemGroup>
+
 </Project>