[core-be-agent]

fix(plugins/test): skip TestLocalResolver_BubblesUpCopyFailure when running as root

Fixes issue #87: the test sets chmod(dst, 0o555) to make the
destination read-only and asserts the copy fails. On Linux, root
bypasses filesystem permissions and can write to 0o555 directories,
so the copy succeeds when running as root and the assertion fails.

Fix: check os.Getuid() == 0 at the start of the test and skip with
a clear message. Mirrors the existing skip in
TestLocalResolver_CopyFileSourceUnreadable (line 175) which already
handles the same root-bypass issue for unreadable source files.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

workspace-server/internal/plugins/local_test.go

@@ -133,7 +133,13 @@ func TestLocalResolver_HonoursContextCancellation(t *testing.T) {
 
 func TestLocalResolver_BubblesUpCopyFailure(t *testing.T) {
 	// Source file the copyTree walk would read; make dst unwritable so
-	// the copyFile step fails.
+	// the copyFile step fails. Skip when running as root — Linux
+	// filesystem permissions are advisory-only for uid 0, so chmod 0o555
+	// does not prevent writes and the test passes vacuously instead of
+	// exercising the error path (issue #87).
+	if os.Getuid() == 0 {
+		t.Skip("skipping: chmod 0o555 is ineffective when running as root")
+	}
 	base := t.TempDir()
 	writePlugin(t, base, "demo", map[string]string{
 		"plugin.yaml": "name: demo\n",