fix: clear mqtt pending commands after startup

water-common/water-common-mqtt/src/test/java/org/dromara/mqtt/MqttPendingCommandCleanupListenerTest.java

@@ -0,0 +1,35 @@
+package org.dromara.mqtt;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Tag;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+
+import static org.assertj.core.api.Assertions.assertThatCode;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@Tag("dev")
+class MqttPendingCommandCleanupListenerTest {
+
+    @Test
+    void onApplicationReadyClearsPendingCommands() {
+        MqttCommandAckService service = mock(MqttCommandAckService.class);
+        when(service.clearPendingCommands()).thenReturn(3);
+        MqttPendingCommandCleanupListener listener = new MqttPendingCommandCleanupListener(service);
+
+        listener.onApplicationReady(mock(ApplicationReadyEvent.class));
+
+        verify(service).clearPendingCommands();
+    }
+
+    @Test
+    void onApplicationReadyDoesNotThrowWhenCleanupFails() {
+        MqttCommandAckService service = mock(MqttCommandAckService.class);
+        when(service.clearPendingCommands()).thenThrow(new IllegalStateException("redis unavailable"));
+        MqttPendingCommandCleanupListener listener = new MqttPendingCommandCleanupListener(service);
+
+        assertThatCode(() -> listener.onApplicationReady(mock(ApplicationReadyEvent.class)))
+            .doesNotThrowAnyException();
+    }
+}