feat(harness): add information gain stop and audit

src/test/java/com/superbiz/agent/config/HarnessChatConfigurationTest.java

@@ -31,6 +31,15 @@ import static org.mockito.Mockito.mock;
 
 class HarnessChatConfigurationTest {
 
+    @Test
+    void diagnosisNoGainThresholdDefaultsAndValidates() {
+        ChatHarnessProperties properties = new ChatHarnessProperties();
+        assertEquals(2, properties.getStopAfterConsecutiveNoGain());
+
+        properties.setStopAfterConsecutiveNoGain(0);
+        assertThrows(IllegalArgumentException.class, properties::validate);
+    }
+
     @Test
     void defaultsArePositiveAndExecutorsAreBounded() {
         ChatHarnessProperties properties = new ChatHarnessProperties();