feat: 多功能升级 — 流式逐字渲染、对话缓存、会话组织优化、记忆管理修复、性能仪表盘

- 前端消息流式逐字渲染 (AI-Core ChatStream → SSE → Gateway → WebSocket stream_chunk → fadeInUp + cursorBlink)
- 后端对话缓存 (conversationCache sync.Map, GET /sessions/:id/messages)
- 前端侧边栏历史多轮对话显示
- DevTools 性能监控图标移至首页仪表盘
- DevTools 用户记忆查询/删减功能修复 (补全 DELETE 数据链路)
- 后端和 DevTools 按用户分类组织实时活动会话 (map[userID]map[sessionID]*Client)
- 新增 docs/api-reference/ 路由参考文档
- 新增 docs/message-flow-architecture.md 消息链路架构文档

devtools/src/performance.js

@@ -103,6 +103,63 @@ class PerformanceMonitor {
     }
     return result;
   }
+
+  /**
+   * 更新仪表盘数据 — 返回聚合的性能摘要供首页仪表盘使用
+   * 调用方负责将数据渲染到 #performance-dashboard 元素
+   * @returns {object} 仪表盘性能摘要
+   */
+  async updateDashboard() {
+    const snapshot = await this.getSnapshot();
+    const entries = Object.entries(snapshot);
+
+    let totalCpu = 0, totalMem = 0, activeCount = 0;
+    for (const [, p] of entries) {
+      totalCpu += p.cpu || 0;
+      totalMem += p.mem || 0;
+      if (p.pid) activeCount++;
+    }
+
+    const avgCpu = entries.length > 0 ? Math.round(totalCpu / entries.length * 10) / 10 : 0;
+    const totalMemRounded = Math.round(totalMem * 100) / 100;
+
+    // 计算平均延迟 (基于各服务进程的 elapsed 时间)
+    let avgLatencyMs = null;
+    let totalElapsed = 0, elapsedCount = 0;
+    for (const [, p] of entries) {
+      if (p.elapsed && p.elapsed > 0) { totalElapsed += p.elapsed; elapsedCount++; }
+    }
+    if (elapsedCount > 0) {
+      avgLatencyMs = Math.round(totalElapsed / elapsedCount);
+    }
+
+    // 获取最近历史用于趋势判断
+    const recentHistory = this.getAllHistory();
+    let trendCpu = 'stable', trendMem = 'stable';
+    for (const [, hist] of Object.entries(recentHistory)) {
+      if (hist.length < 5) continue;
+      const recent = hist.slice(-5);
+      const firstCpu = recent[0].cpu, lastCpu = recent[recent.length - 1].cpu;
+      const firstMem = recent[0].mem, lastMem = recent[recent.length - 1].mem;
+      if (lastCpu > firstCpu * 1.15) trendCpu = 'up';
+      else if (lastCpu < firstCpu * 0.85) trendCpu = 'down';
+      if (lastMem > firstMem * 1.15) trendMem = 'up';
+      else if (lastMem < firstMem * 0.85) trendMem = 'down';
+    }
+
+    return {
+      timestamp: Date.now(),
+      summary: {
+        avgCpu,
+        totalMemMB: totalMemRounded,
+        activeProcesses: activeCount,
+        monitoredServices: entries.length,
+        avgLatencyMs,
+        trend: { cpu: trendCpu, mem: trendMem },
+      },
+      perService: snapshot,
+    };
+  }
 }
 
 export const performanceMonitor = new PerformanceMonitor();