feat: 完善循环输出扁平聚合

- 校验并恢复循环输出的聚合策略

- 将最终类型并入参数值并优化同排开关交互

easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/event/WorkflowExecutionAuditConsumerTest.java

@@ -627,11 +627,11 @@ public class WorkflowExecutionAuditConsumerTest {
         loopRepository.append(
                 resultId,
                 0,
-                Map.of("answer", "first"));
+                Map.of("answer", List.of("first", "second")));
         loopRepository.append(
                 resultId,
                 1,
-                Map.of("answer", "second"));
+                Map.of("answer", List.of("third")));
         WorkflowExecutionAuditConsumer consumer =
                 new WorkflowExecutionAuditConsumer(
                         resultService,
@@ -650,7 +650,8 @@ public class WorkflowExecutionAuditConsumerTest {
                         new LoopResultReference(
                                 resultId,
                                 2,
-                                "answer"));
+                                "answer",
+                                true));
         WorkflowExecStep incomingStep =
                 new WorkflowExecStep();
         incomingStep.setExecKey("step-loop");
@@ -700,10 +701,10 @@ public class WorkflowExecutionAuditConsumerTest {
                         resultCaptor.getValue().getOutput(),
                         Map.class);
         Assert.assertEquals(
-                List.of("first", "second"),
+                List.of("first", "second", "third"),
                 stepOutput.get("answers"));
         Assert.assertEquals(
-                List.of("first", "second"),
+                List.of("first", "second", "third"),
                 resultOutput.get("answers"));
     }
 

easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckServiceTest.java

@@ -221,6 +221,55 @@ public class WorkflowCheckServiceTest {
         assertHasCode(result, "EXPLICIT_LOOP_ITEMS_TYPE_INVALID");
     }
 
+    /**
+     * 验证循环数组输出允许启用扁平聚合。
+     */
+    @Test
+    public void testSaveShouldPassArrayLoopOutputFlattenAggregation() throws Exception {
+        WorkflowCheckService service = newService(new HashMap<>());
+        JSONObject loopData = loopData(
+                fixedParameter("count", "2", "Number"), null);
+        JSONObject output = refParameter(
+                "res",
+                "knowledge.documents.content",
+                "Array<String>");
+        output.put("flattenAggregation", true);
+        loopData.put("outputDefs", array(output));
+        String content = workflowJson(
+                array(node("loop-1", "loopNode", null, loopData)),
+                new JSONArray());
+
+        WorkflowCheckResult result = service.checkContent(
+                content, WorkflowCheckStage.SAVE, null);
+
+        Assert.assertTrue(result.isPassed());
+    }
+
+    /**
+     * 验证循环标量输出不能启用扁平聚合。
+     */
+    @Test
+    public void testSaveShouldBlockScalarLoopOutputFlattenAggregation() throws Exception {
+        WorkflowCheckService service = newService(new HashMap<>());
+        JSONObject loopData = loopData(
+                fixedParameter("count", "2", "Number"), null);
+        JSONObject output = refParameter(
+                "res",
+                "child.output",
+                "String");
+        output.put("flattenAggregation", true);
+        loopData.put("outputDefs", array(output));
+        String content = workflowJson(
+                array(node("loop-1", "loopNode", null, loopData)),
+                new JSONArray());
+
+        WorkflowCheckResult result = service.checkContent(
+                content, WorkflowCheckStage.SAVE, null);
+
+        Assert.assertFalse(result.isPassed());
+        assertHasCode(result, "LOOP_OUTPUT_FLATTEN_TYPE_INVALID");
+    }
+
     /**
      * 验证新旧循环输入不能同时提交。
      */