Honor cancellation throughout publication recovery Git operations

internal/git/source.go

@@ -73,6 +73,28 @@ func MetadataDirectories(ctx context.Context, directory string) ([]string, error
 	return directories, nil
 }
 
+// CommonDirectory resolves the shared Git metadata directory.
+func CommonDirectory(ctx context.Context, directory string) (string, error) {
+	output, err := run(ctx, directory, nil, "rev-parse", "--path-format=absolute", "--git-common-dir")
+	if err != nil {
+		return "", fmt.Errorf("resolve shared Git metadata directory: %w", err)
+	}
+	return normalizeRepositoryRoot(output)
+}
+
+// IsIgnored checks whether Git excludes the selected worktree path.
+func IsIgnored(ctx context.Context, directory, path string) (bool, error) {
+	_, err := run(ctx, directory, nil, "check-ignore", "-q", "--", path)
+	if err == nil {
+		return true, nil
+	}
+	var exitErr *exec.ExitError
+	if errors.As(err, &exitErr) && exitErr.ExitCode() == 1 {
+		return false, nil
+	}
+	return false, err
+}
+
 // DiscoverRepositoryRoot finds a containing checkout or confirms standalone use.
 func DiscoverRepositoryRoot(ctx context.Context, directory string) (string, bool, error) {
 	if directory == "" {