refactor: remove generic mqtt enable alias

modules/inbound/inbound-mqtt/src/main/java/com/lingniu/ingest/inbound/mqtt/config/MqttInboundEnabledCondition.java

@@ -14,8 +14,7 @@ final class MqttInboundEnabledCondition implements Condition {
         if (direct != null) {
             return direct;
         }
-        return isTrue(env.getProperty("MQTT_ENABLED"))
-                || isTrue(env.getProperty("YUTONG_MQTT_ENABLED"));
+        return isTrue(env.getProperty("YUTONG_MQTT_ENABLED"));
     }
 
     private static boolean isTrue(String value) {

modules/inbound/inbound-mqtt/src/test/java/com/lingniu/ingest/inbound/mqtt/config/MqttInboundEnabledConditionTest.java

@@ -0,0 +1,68 @@
+package com.lingniu.ingest.inbound.mqtt.config;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.context.annotation.ConditionContext;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.core.env.StandardEnvironment;
+import org.springframework.core.io.ResourceLoader;
+
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class MqttInboundEnabledConditionTest {
+
+    private final MqttInboundEnabledCondition condition = new MqttInboundEnabledCondition();
+
+    @Test
+    void ignoresLegacyGenericMqttEnabledEnvironmentAlias() {
+        assertThat(condition.matches(context(Map.of("MQTT_ENABLED", "true")), null)).isFalse();
+    }
+
+    @Test
+    void acceptsYutongMqttEnabledEnvironmentAlias() {
+        assertThat(condition.matches(context(Map.of("YUTONG_MQTT_ENABLED", "true")), null)).isTrue();
+    }
+
+    @Test
+    void directPropertyOverridesEnvironmentAlias() {
+        assertThat(condition.matches(context(Map.of(
+                "lingniu.ingest.mqtt.enabled", "false",
+                "YUTONG_MQTT_ENABLED", "true")), null)).isFalse();
+    }
+
+    private static ConditionContext context(Map<String, Object> properties) {
+        StandardEnvironment environment = new StandardEnvironment();
+        environment.getPropertySources().addFirst(new MapPropertySource("test", properties));
+        return new TestConditionContext(environment);
+    }
+
+    private record TestConditionContext(StandardEnvironment environment) implements ConditionContext {
+        @Override
+        public BeanDefinitionRegistry getRegistry() {
+            return null;
+        }
+
+        @Override
+        public ConfigurableListableBeanFactory getBeanFactory() {
+            return null;
+        }
+
+        @Override
+        public StandardEnvironment getEnvironment() {
+            return environment;
+        }
+
+        @Override
+        public ResourceLoader getResourceLoader() {
+            return null;
+        }
+
+        @Override
+        public ClassLoader getClassLoader() {
+            return null;
+        }
+    }
+}