fix workspace output and cleanup uncertainty

tools/thothctl/internal/safeio/files_windows_test.go

@@ -125,6 +125,34 @@ func TestWindowsStageHandleDeniesReadRenameDeleteAndHardlink(t *testing.T) {
 	}
 }
 
+func TestWriteCanonicalExclusiveClassifiesDispositionFailureAsIndeterminate(t *testing.T) {
+	root := t.TempDir()
+	path := filepath.Join(root, "candidate.yaml")
+	if err := os.WriteFile(path, []byte("existing"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	oldDelete, oldClose := windowsDeleteHandle, windowsCloseStage
+	t.Cleanup(func() { windowsDeleteHandle, windowsCloseStage = oldDelete, oldClose })
+	windowsDeleteHandle = func(windows.Handle) error { return errors.New("injected disposition failure") }
+	if err := writeCanonicalExclusive(path, []byte("candidate"), 0o600); !errors.Is(err, ErrIndeterminateFile) {
+		t.Fatalf("disposition failure = %v, want ErrIndeterminateFile", err)
+	}
+}
+
+func TestWriteCanonicalExclusiveClassifiesCloseFailureAsIndeterminate(t *testing.T) {
+	root := t.TempDir()
+	path := filepath.Join(root, "candidate.yaml")
+	if err := os.WriteFile(path, []byte("existing"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	oldDelete, oldClose := windowsDeleteHandle, windowsCloseStage
+	t.Cleanup(func() { windowsDeleteHandle, windowsCloseStage = oldDelete, oldClose })
+	windowsCloseStage = func(*os.File) error { return errors.New("injected close failure") }
+	if err := writeCanonicalExclusive(path, []byte("candidate"), 0o600); !errors.Is(err, ErrIndeterminateFile) {
+		t.Fatalf("close failure = %v, want ErrIndeterminateFile", err)
+	}
+}
+
 func TestWriteCanonicalExclusiveRequiresRestrictiveMode(t *testing.T) {
 	if err := writeCanonicalExclusive(`C:\\tmp\\thothctl-output.yaml`, []byte("x"), 0o640); err == nil {
 		t.Fatal("accepted non-restrictive output mode")