fix: 第二轮修复 — 数据库启动检查、会话持久化、URL路由、设备排序等

1. DevTools 启动前检查数据库状态，失败时自动尝试启动
2. ai-core 添加数据库断线重连机制 (30秒间隔)
3. Dashboard 添加数据库状态卡片 (启动/停止/重启)
4. Gateway 会话空闲超时管理 (30分钟标记空闲)
5. 会话/消息 PostgreSQL 持久化 (SessionStore + REST API)
6. 前端服务端会话持久化 + URL hash 路由 + 侧边栏管理
7. 管理员回到主对话按钮
8. IoT 设备卡片固定排序
9. 更新相关文档

devtools/src/index.js

@@ -696,6 +696,82 @@ app.post('/api/tunnel/:action', (req, res) => {
   }
 });
 
+// ---- 数据库控制 (Docker Compose) ----
+const DB_COMPOSE_FILE = path.join(ROOT, 'docker-compose.dev.db.yml');
+const DB_PORT = 5432;
+
+// GET /api/db/status
+app.get('/api/db/status', (_req, res) => {
+  try {
+    const online = checkPort(DB_PORT);
+    res.json({
+      online,
+      port: DB_PORT,
+      checked_at: new Date().toISOString(),
+    });
+  } catch (err) {
+    res.json({
+      online: false,
+      port: DB_PORT,
+      checked_at: new Date().toISOString(),
+    });
+  }
+});
+
+// POST /api/db/start
+app.post('/api/db/start', (_req, res) => {
+  try {
+    const out = execSync(`docker compose -f "${DB_COMPOSE_FILE}" up -d`, {
+      encoding: 'utf-8',
+      timeout: 60000,
+      stdio: 'pipe',
+    });
+    res.json({ success: true, action: 'start', output: out.trim() });
+  } catch (err) {
+    const stderr = err.stderr?.toString() || err.message;
+    res.status(500).json({ success: false, action: 'start', error: stderr });
+  }
+});
+
+// POST /api/db/stop
+app.post('/api/db/stop', (_req, res) => {
+  try {
+    const out = execSync(`docker compose -f "${DB_COMPOSE_FILE}" down`, {
+      encoding: 'utf-8',
+      timeout: 30000,
+      stdio: 'pipe',
+    });
+    res.json({ success: true, action: 'stop', output: out.trim() });
+  } catch (err) {
+    const stderr = err.stderr?.toString() || err.message;
+    res.status(500).json({ success: false, action: 'stop', error: stderr });
+  }
+});
+
+// POST /api/db/restart
+app.post('/api/db/restart', (_req, res) => {
+  try {
+    const downOut = execSync(`docker compose -f "${DB_COMPOSE_FILE}" down`, {
+      encoding: 'utf-8',
+      timeout: 30000,
+      stdio: 'pipe',
+    });
+    const upOut = execSync(`docker compose -f "${DB_COMPOSE_FILE}" up -d`, {
+      encoding: 'utf-8',
+      timeout: 60000,
+      stdio: 'pipe',
+    });
+    res.json({
+      success: true,
+      action: 'restart',
+      output: `down: ${downOut.trim()}\nup: ${upOut.trim()}`,
+    });
+  } catch (err) {
+    const stderr = err.stderr?.toString() || err.message;
+    res.status(500).json({ success: false, action: 'restart', error: stderr });
+  }
+});
+
 // ========== 启动 ==========
 // 启动性能监控
 performanceMonitor.start();