fix: 兼容旧模型内联思考标签

- 在结构化 reasoning 为空时解析正文开头的 think/thinking 标签

- 将思考与正文映射为现有流式事件并覆盖 Agent 与 Bot 链路

- 补充跨分片和旁路条件测试

easyflow-modules/easyflow-module-agent/src/test/java/tech/easyflow/agent/runtime/AgentRunServiceDraftAndHitlTest.java

@@ -32,6 +32,7 @@ import tech.easyflow.core.runtime.ChatAssistantAccumulator;
 import tech.easyflow.core.runtime.ChatRuntimeContext;
 import tech.easyflow.core.runtime.ChatRuntimeManager;
 import tech.easyflow.core.runtime.ChatRuntimeMessage;
+import tech.easyflow.core.runtime.LegacyThinkingTagParser;
 
 import java.lang.reflect.Method;
 import java.math.BigInteger;
@@ -176,6 +177,59 @@ public class AgentRunServiceDraftAndHitlTest {
         Assert.assertEquals("正文增量", payload.get("delta"));
     }
 
+    /**
+     * 验证旧模型写入 content 的思考标签即使跨增量拆分，也会转换为结构化思考事件。
+     *
+     * @throws Exception 反射调用失败时抛出
+     */
+    @Test
+    public void handleRuntimeEventShouldSplitLegacyThinkingTagsAcrossDeltas() throws Exception {
+        AgentRunService service = new AgentRunService();
+        setField(service, "agentRunRegistry", new AgentRunRegistry());
+        RecordingChatSseEmitter emitter = new RecordingChatSseEmitter();
+        StringBuilder answer = new StringBuilder();
+        ChatAssistantAccumulator assistantAccumulator = new ChatAssistantAccumulator();
+        LegacyThinkingTagParser parser = new LegacyThinkingTagParser();
+        AtomicBoolean finished = new AtomicBoolean(false);
+
+        for (String delta : List.of("<thi", "nk>先分析</thi", "nk>\n最终回答")) {
+            AgentRuntimeEvent event = AgentRuntimeEvent.of(AgentRuntimeEventType.MESSAGE_DELTA);
+            event.getPayload().put("text", delta);
+            invoke(service, "handleRuntimeEvent",
+                    legacyRuntimeEventParameterTypes(),
+                    event, "request-legacy-thinking", emitter, answer, assistantAccumulator,
+                    parser, chatContext(), finished, false);
+        }
+
+        AgentRuntimeEvent completed = AgentRuntimeEvent.of(AgentRuntimeEventType.COMPLETED);
+        completed.getPayload().put("text", "<think>先分析</think>\n最终回答");
+        invoke(service, "handleRuntimeEvent",
+                legacyRuntimeEventParameterTypes(),
+                completed, "request-legacy-thinking", emitter, answer, assistantAccumulator,
+                parser, chatContext(), finished, false);
+
+        StringBuilder reasoning = new StringBuilder();
+        StringBuilder content = new StringBuilder();
+        for (ChatEnvelope<?> envelope : emitter.envelopes) {
+            if (envelope.getDomain() != ChatDomain.LLM) {
+                continue;
+            }
+            @SuppressWarnings("unchecked")
+            Map<String, Object> payload = (Map<String, Object>) envelope.getPayload();
+            if (envelope.getType() == ChatType.THINKING) {
+                reasoning.append(payload.get("delta"));
+            } else if (envelope.getType() == ChatType.MESSAGE) {
+                content.append(payload.get("delta"));
+            }
+        }
+
+        Assert.assertEquals("先分析", reasoning.toString());
+        Assert.assertEquals("\n最终回答", content.toString());
+        Assert.assertEquals("\n最终回答", answer.toString());
+        Assert.assertTrue(emitter.envelopes.stream().anyMatch(envelope ->
+                envelope.getDomain() == ChatDomain.SYSTEM && envelope.getType() == ChatType.DONE));
+    }
+
     /**
      * 验证自动上下文压缩事件会作为业务状态发送给前端。
      *
@@ -809,6 +863,12 @@ public class AgentRunServiceDraftAndHitlTest {
                 ChatRuntimeContext.class, AtomicBoolean.class, boolean.class};
     }
 
+    private Class<?>[] legacyRuntimeEventParameterTypes() {
+        return new Class<?>[]{AgentRuntimeEvent.class, String.class, ChatSseEmitter.class, StringBuilder.class,
+                ChatAssistantAccumulator.class, LegacyThinkingTagParser.class,
+                ChatRuntimeContext.class, AtomicBoolean.class, boolean.class};
+    }
+
     private AgentRunRegistry.AgentRunContext runContext(String requestId, String sessionId, boolean persistChatlog) {
         return new AgentRunRegistry.AgentRunContext(
                 requestId,