feat(kb): VikingDB纯检索+重排+Redis上下文+全库搜索+别名扩展+KB保护窗口+RAG语气引导

- 新增 kbRetriever.js: VikingDB search_knowledge 纯检索替代 Ark chat/completions, doubao-seed-rerank 重排, RAG payload 语气引导缓解音色差异

- 新增 redisClient.js: Redis 连接管理 + 5轮对话历史 + KB缓存双写

- toolExecutor.js: 产品别名扩展25条, 全库检索topK=25, 检索阈值0.01, 精简 buildDeterministicKnowledgeQuery

- nativeVoiceGateway.js: isPureChitchat扩展, KB保护窗口60s, prequery参数调优

- realtimeDialogRouting.js: resolveReply感知KB保护窗口, fast-path适配raw模式

- app.js: 健康检查新增 redis/reranker/kbRetrievalMode

- 新增测试: alias A/B测试, KB retriever测试, Redis客户端测试, raw模式集成测试

test2/server/app.js

@@ -9,6 +9,7 @@ const voiceRoutes = require('./routes/voice');
 const chatRoutes = require('./routes/chat');
 const sessionRoutes = require('./routes/session');
 const { setupNativeVoiceGateway } = require('./services/nativeVoiceGateway');
+const redisClient = require('./services/redisClient');
 
 // ========== 环境变量校验 ==========
 function validateEnv() {
@@ -54,6 +55,8 @@ function validateEnv() {
     { key: 'VOLC_S2S_SPEAKER_ID', desc: '自定义音色' },
     { key: 'VOLC_ARK_KNOWLEDGE_BASE_IDS', desc: '方舟私域知识库（语音）' },
     { key: 'ASSISTANT_PROFILE_API_URL', desc: '外接助手资料接口' },
+    { key: 'REDIS_URL', desc: 'Redis（对话上下文+KB缓存）' },
+    { key: 'ENABLE_RERANKER', desc: '重排模型' },
   ];
   const configuredOptional = optional.filter(({ key }) => {
     const v = process.env[key];
@@ -107,6 +110,9 @@ app.get('/api/health', (req, res) => {
     webSearch: !!process.env.VOLC_WEBSEARCH_API_KEY && !process.env.VOLC_WEBSEARCH_API_KEY.startsWith('your_'),
     customSpeaker: !!process.env.VOLC_S2S_SPEAKER_ID && !process.env.VOLC_S2S_SPEAKER_ID.startsWith('your_'),
     arkKnowledgeBase: !!process.env.VOLC_ARK_KNOWLEDGE_BASE_IDS && !process.env.VOLC_ARK_KNOWLEDGE_BASE_IDS.startsWith('your_'),
+    redis: redisClient.isAvailable(),
+    reranker: process.env.ENABLE_RERANKER === 'true' ? (process.env.VOLC_ARK_RERANKER_MODEL || 'doubao-seed-rerank') : false,
+    kbRetrievalMode: process.env.VOLC_ARK_KB_RETRIEVAL_MODE || 'answer',
   },
   });
 });
@@ -144,6 +150,15 @@ async function start() {
     console.warn('[DB] Continuing without database — context switching will use in-memory fallback');
   }
 
+  // Redis 初始化（可选，失败不阻塞启动）
+  try {
+    redisClient.createClient();
+    console.log('[Redis] Client created, connecting...');
+  } catch (err) {
+    console.warn('[Redis] Initialization failed:', err.message);
+    console.warn('[Redis] Continuing without Redis — will use in-memory fallback');
+  }
+
   if (process.env.ENABLE_NATIVE_VOICE_GATEWAY !== 'false') {
     setupNativeVoiceGateway(server);
     console.log('[NativeVoice] Gateway enabled at /ws/realtime-dialog');