feat: conversation long-term memory + fix source ENUM bug

- New: conversationSummarizer.js (LLM summary every 3 turns, loadBestSummary, persistFinalSummary)
- db/index.js: conversation_summaries table, upsertConversationSummary, getSessionSummary
- redisClient.js: setSummary/getSummary (TTL 2h)
- nativeVoiceGateway.js: _turnCount tracking, trigger summarize, persist on close
- realtimeDialogRouting.js: inject summary context, reduce history 5->3 rounds
- Fix: messages source ENUM missing 'search_knowledge' causing chat DB writes to fail

test2/server/services/redisClient.js

@@ -10,6 +10,7 @@ const HISTORY_MAX_LEN = 10; // 5轮 × 2条/轮
 const HISTORY_TTL_S = 1800; // 30分钟
 const KB_CACHE_HIT_TTL_S = 300; // 5分钟
 const KB_CACHE_NOHIT_TTL_S = 120; // 2分钟
+const SUMMARY_TTL_S = parseInt(process.env.SUMMARY_REDIS_TTL_SECONDS) || 7200; // 2小时
 
 // ============ 连接管理 ============
 let client = null;
@@ -128,6 +129,32 @@ async function clearSession(sessionId) {
   }
 }
 
+// ============ 对话摘要 ============
+const summaryKey = (sessionId) => `voice:summary:${sessionId}`;
+
+async function setSummary(sessionId, summary) {
+  if (!isAvailable() || !summary) return false;
+  try {
+    const key = summaryKey(sessionId);
+    await client.set(key, summary, 'EX', SUMMARY_TTL_S);
+    return true;
+  } catch (err) {
+    console.warn('[Redis] setSummary failed:', err.message);
+    return false;
+  }
+}
+
+async function getSummary(sessionId) {
+  if (!isAvailable()) return null;
+  try {
+    const key = summaryKey(sessionId);
+    return await client.get(key);
+  } catch (err) {
+    console.warn('[Redis] getSummary failed:', err.message);
+    return null;
+  }
+}
+
 // ============ KB 缓存 ============
 const kbCacheKey = (cacheKey) => `kb_cache:${cacheKey}`;
 
@@ -178,6 +205,8 @@ module.exports = {
   pushMessage,
   getRecentHistory,
   clearSession,
+  setSummary,
+  getSummary,
   setKbCache,
   getKbCache,
   disconnect,