feat(saas): Phase 4 端到端完善 — 设备注册、离线支持、配置迁移、集成测试

- 后端: devices 表 + register/heartbeat/list 端点 (UPSERT 语义)
- 桌面端: 设备 ID 持久化 + 5 分钟心跳 + 离线状态指示
- saas-client: 重试逻辑 (2 次指数退避) + isServerReachable 跟踪
- ConfigMigrationWizard: 3 步向导 (方向选择→冲突解决→结果)
- SaaSSettings: 修改密码折叠面板 + 迁移向导入口
- 集成测试: 21 个测试全部通过 (含设备注册/UPSERT/心跳、密码修改、E2E 生命周期)
- 修复 ConfigMigrationWizard merge 分支变量遮蔽 bug

desktop/src/store/saasStore.ts

@@ -28,6 +28,20 @@ import { createLogger } from '../lib/logger';
 
 const log = createLogger('SaaSStore');
 
+// === Device ID ===
+
+/** Generate or load a persistent device ID for this browser instance */
+function getOrCreateDeviceId(): string {
+  const KEY = 'zclaw-device-id';
+  const existing = localStorage.getItem(KEY);
+  if (existing) return existing;
+  const newId = crypto.randomUUID();
+  localStorage.setItem(KEY, newId);
+  return newId;
+}
+
+const DEVICE_ID = getOrCreateDeviceId();
+
 // === Types ===
 
 export type ConnectionMode = 'tauri' | 'gateway' | 'saas';
@@ -49,6 +63,7 @@ export interface SaaSActionsSlice {
   logout: () => void;
   setConnectionMode: (mode: ConnectionMode) => void;
   fetchAvailableModels: () => Promise<void>;
+  registerCurrentDevice: () => Promise<void>;
   clearError: () => void;
   restoreSession: () => void;
 }
@@ -138,6 +153,11 @@ export const useSaaSStore = create<SaaSStore>((set, get) => {
           error: null,
         });
 
+        // Register device and start heartbeat in background
+        get().registerCurrentDevice().catch((err: unknown) => {
+          log.warn('Failed to register device:', err);
+        });
+
         // Fetch available models in background (non-blocking)
         get().fetchAvailableModels().catch((err: unknown) => {
           log.warn('Failed to fetch models after login:', err);
@@ -209,6 +229,10 @@ export const useSaaSStore = create<SaaSStore>((set, get) => {
           error: null,
         });
 
+        get().registerCurrentDevice().catch((err: unknown) => {
+          log.warn('Failed to register device after register:', err);
+        });
+
         get().fetchAvailableModels().catch((err: unknown) => {
           log.warn('Failed to fetch models after register:', err);
         });
@@ -271,6 +295,41 @@ export const useSaaSStore = create<SaaSStore>((set, get) => {
       }
     },
 
+    registerCurrentDevice: async () => {
+      const { isLoggedIn, authToken, saasUrl } = get();
+
+      if (!isLoggedIn || !authToken) {
+        return;
+      }
+
+      try {
+        saasClient.setBaseUrl(saasUrl);
+        saasClient.setToken(authToken);
+        await saasClient.registerDevice({
+          device_id: DEVICE_ID,
+          device_name: `${navigator.userAgent.split(' ').slice(0, 3).join(' ')}`,
+          platform: navigator.platform,
+          app_version: __APP_VERSION__ || 'unknown',
+        });
+        log.info('Device registered successfully');
+
+        // Start periodic heartbeat (every 5 minutes)
+        if (typeof window !== 'undefined' && !get()._heartbeatTimer) {
+          const timer = window.setInterval(() => {
+            const state = get();
+            if (state.isLoggedIn && state.authToken) {
+              saasClient.deviceHeartbeat(DEVICE_ID).catch(() => {});
+            } else {
+              window.clearInterval(timer);
+            }
+          }, 5 * 60 * 1000);
+          set({ _heartbeatTimer: timer } as unknown as Partial<SaaSStore>);
+        }
+      } catch (err: unknown) {
+        log.warn('Failed to register device:', err);
+      }
+    },
+
     clearError: () => {
       set({ error: null });
     },