意图识别与问题改写的流水线编排

public Mono<Msg> executeFullPipeline(List<Msg> inputMessages, String sessionId, String userId) {
    String originalQuestion = extractLatestUserText(inputMessages);

    // 阶段一：先用【原始问题】做 L1/L2 快速识别（router.route 不触发 L3）
    return Mono.fromCallable(() -> intentRecognitionRouter.route(originalQuestion))
            .subscribeOn(Schedulers.boundedElastic())
            .flatMap(fastHit -> {
                if (fastHit.isPresent()) {
                    // 命中：跳过问题改写，直接调度
                    String intentJson = JSON.toJSONString(fastHit.get().toJsonMap());
                    logger.info("[PIPELINE] L1/L2 命中，跳过问题改写，直接调度: {}", intentJson);
                    // 快路径没真正调用 QueryRewritingAgent，补一条"影子历史"写回 Session，
                    // 以免下一轮未命中 L1/L2 时改写 Agent 看不到本轮上下文
                    appendQueryRewritingShadowHistory(sessionId, originalQuestion);
                    return dispatchByIntent(intentJson, inputMessages, originalQuestion, sessionId, userId);
                }
                // 未命中：阶段二——先问题改写，再走完整 L1/L2/L3
                return rewriteThenRecognizeAndDispatch(inputMessages, sessionId, userId);
            });
}

    /**
     * L1/L2 未命中时的降级流程：问题改写（QueryRewritingAgent）→ 重新意图识别
     * （IntentRecognitionAgent，此时走完整 L1/L2/L3）→ 调度。
     */
    private Mono<Msg> rewriteThenRecognizeAndDispatch(List<Msg> inputMessages, String sessionId, String userId) {
        QueryRewritingAgent queryRewritingAgent = agentRegistry.getQueryRewriter();
        IntentRecognitionAgent intentRecognitionAgent = agentRegistry.getIntentRecognizer();

        return queryRewritingAgent.call(inputMessages)
                .doOnSubscribe(s -> executionRegistry.register(sessionId, queryRewritingAgent))
                .flatMap(rewriteResult -> {
                    if (isInterruptRecovery(rewriteResult)) {
                        logger.info("[PIPELINE] QueryRewritingAgent 被优雅中断，终止流水线并返回中文提示");
                        return Mono.just(buildInterruptRecoveryMsg());
                    }
                    String rewrittenQuestion = parseRewrittenQuestion(rewriteResult.getTextContent());
                    logger.info("[PIPELINE] 问题改写完成: {}", rewrittenQuestion);
                    return intentRecognitionAgent.call(buildIntentInput(rewrittenQuestion))
                            .doOnSubscribe(s -> executionRegistry.register(sessionId, intentRecognitionAgent))
                            .flatMap(intentResult -> {
                                if (isInterruptRecovery(intentResult)) {
                                    logger.info("[PIPELINE] IntentRecognitionAgent 被优雅中断，终止流水线并返回中文提示");
                                    return Mono.just(buildInterruptRecoveryMsg());
                                }
                                String intentJson = intentResult.getTextContent();
                                logger.info("[PIPELINE] 意图识别完成: {}", intentJson);
                                conversationTitleService.updateTitleAsync(sessionId, userId, rewrittenQuestion, intentJson);
                                return dispatchByIntent(intentJson, inputMessages, rewrittenQuestion, sessionId, userId);
                            });
                });
    }