exclude PackageOutputPath (#744)

1. DocoTask.cs (line 27): Added PackageOutputPath property. In Execute() (lines 34-38), if set, it resolves the path
  relative to ProjectDirectory and adds it to ExcludeDirs before the exclusion filters are built.
  2. MarkdownSnippets.MsBuild.targets (line 23): Passes $(PackageOutputPath) from the MSBuild context to the task.

  When a project sets <PackageOutputPath>nugets</PackageOutputPath>, MSBuild passes that value to the task, which
  resolves it to an absolute path and adds it to the directory exclusion list — preventing the scanner from trying to
  read locked .nuspec/.nupkg files in that directory.

Author: SimonCropp

src/MarkdownSnippets.MsBuild/DocoTask.cs

@@ -24,11 +24,19 @@ public class DocoTask :
     public List<string> UrlsAsSnippets { get; set; } = [];
     public bool? TreatMissingAsWarning { get; set; }
     public bool? OmitSnippetLinks { get; set; }
+    public string? PackageOutputPath { get; set; }
 
     public override bool Execute()
     {
         var stopwatch = Stopwatch.StartNew();
         var root = GitRepoDirectoryFinder.FindForDirectory(ProjectDirectory);
+
+        if (!string.IsNullOrWhiteSpace(PackageOutputPath))
+        {
+            var resolved = Path.GetFullPath(Path.Combine(ProjectDirectory, PackageOutputPath));
+            ExcludeDirs.Add(resolved);
+        }
+
         var (fileConfig, configFilePath) = ConfigReader.Read(root);
 
         var configResult = ConfigDefaults.Convert(

src/MarkdownSnippets.MsBuild/MarkdownSnippets.MsBuild.targets

@@ -19,6 +19,7 @@
     <MarkdownSnippets.DocoTask
       ProjectDirectory="$(MSBuildProjectDirectory)"
       ReadOnly="$(MarkdownSnippetsReadOnly)"
-      WriteHeader="$(MarkdownSnippetsWriteHeader)" />
+      WriteHeader="$(MarkdownSnippetsWriteHeader)"
+      PackageOutputPath="$(PackageOutputPath)" />
   </Target>
 </Project>