Fix managed process helper command serialization

runtime/lifecycle.go

@@ -926,7 +926,7 @@ type ProcessCommand struct {
 	JobID      string
 	Capability string
 	Action     string
-	OutputLine func(string, string)
+	OutputLine func(string, string) `json:"-"`
 }
 
 type ProcessResult struct {

runtime/lifecycle_test.go

@@ -569,6 +569,22 @@ func TestOSProcessSupervisorRelaysRawCarriageReturn(t *testing.T) {
 	}
 }
 
+func TestProcessCommandJSONOmitsOutputCallback(t *testing.T) {
+	body, err := json.Marshal(ProcessCommand{
+		WorkDir: "/workspace",
+		Args:    []string{"cmd.exe", "/d", "/c", "call", "start.cmd"},
+		OutputLine: func(stream string, line string) {
+			panic(stream + line)
+		},
+	})
+	if err != nil {
+		t.Fatalf("marshal process command with output callback: %v", err)
+	}
+	if strings.Contains(string(body), "OutputLine") || strings.Contains(string(body), "func") {
+		t.Fatalf("output callback leaked into helper JSON: %s", body)
+	}
+}
+
 type recordingLogSink struct {
 	mu    sync.Mutex
 	lines []string