feat(sdk): support NuGet Central Package Management

Remove implicit PackageReference for Microsoft.VSSDK.BuildTools from
the SDK. This allows projects using NuGet Central Package Management
(CPM) to work correctly, as CPM requires PackageReference items to not
have a Version attribute when versions are centrally managed.

Users must now explicitly add the PackageReference in their project:

  <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />

This is a breaking change but aligns with CPM compatibility requirements.

Closes #27

Author: CalvinAllen

README.md

@@ -104,6 +104,7 @@ Replace your entire `.csproj` file with the SDK-style format:
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 </Project>
 ```
@@ -135,12 +136,11 @@ Convert from `packages.config` to `PackageReference` format in your `.csproj`:
 ```xml
 <ItemGroup>
   <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+  <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   <!-- Add other packages your extension uses -->
 </ItemGroup>
 ```
 
-> **Note:** `Microsoft.VSSDK.BuildTools` is automatically included by the SDK.
-
 #### Step 6: Handle VSCT Files
 
 If you have `.vsct` files, they're automatically included. Remove any explicit `<VSCTCompile>` items unless you need custom metadata.
@@ -179,6 +179,7 @@ If you prefer to set up manually, create a `.csproj` file:
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 </Project>
 ```

samples/SampleExtension/SampleExtension.csproj

@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
 </Project>

src/CodingWithCalvin.VsixSdk/Sdk/Sdk.Vsix.props

@@ -17,18 +17,6 @@
               Condition="Exists('$(MSBuildThisFileDirectory)..\analyzers\dotnet\cs\CodingWithCalvin.VsixSdk.Generators.dll')" />
   </ItemGroup>
 
-  <!--
-    Implicit package references for VSIX development.
-    Users can override the version by setting VssdkBuildToolsVersion before SDK import.
-  -->
-  <PropertyGroup>
-    <VssdkBuildToolsVersion Condition="'$(VssdkBuildToolsVersion)' == ''">17.*</VssdkBuildToolsVersion>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="$(VssdkBuildToolsVersion)" PrivateAssets="all" />
-  </ItemGroup>
-
   <PropertyGroup>
     <!-- Identify that this SDK is in use -->
     <UsingCodingWithCalvinVsixSdk>true</UsingCodingWithCalvinVsixSdk>

tests/e2e/E2E.AllFeatures/E2E.AllFeatures.csproj

@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- Manual template with subpath -->

tests/e2e/E2E.AutoIncludes/E2E.AutoIncludes.csproj

@@ -15,6 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
 </Project>

tests/e2e/E2E.CustomPkgDef/E2E.CustomPkgDef.csproj

@@ -14,6 +14,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- Include custom pkgdef files to merge with auto-generated -->

tests/e2e/E2E.ImageAndContentManifest/E2E.ImageAndContentManifest.csproj

@@ -14,6 +14,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
 </Project>

tests/e2e/E2E.ManualPkgDef/E2E.ManualPkgDef.csproj

@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- Use manual pkgdef file -->

tests/e2e/E2E.Minimal/E2E.Minimal.csproj

@@ -15,6 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
 </Project>

tests/e2e/E2E.SourceGenerators/E2E.SourceGenerators.csproj

@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.SDK" Version="17.*" />
+    <PackageReference Include="Microsoft.VSSDK.BuildTools" Version="17.*" PrivateAssets="all" />
   </ItemGroup>
 
   <!-- Include assets referenced in manifest -->