fix: 修复 AI 设计会话失效后的伪登录

问题：Main 刷新令牌返回 401 后已清空会话，但 Renderer 仍保留用户信息，AI 设计持续返回 AUTH_REQUIRED。

实现：认证初始化等待 Main 同步完成；同步或刷新失败清理登录态；Workspace 识别结构化认证错误并在重新登录后恢复加载；路由守卫响应登录状态变化。

验证：49 个聚焦测试通过，TypeScript、聚焦 Lint 与 Vite 生产构建通过。

src/pages/ImageCanvas/index.tsx

@@ -27,6 +27,7 @@ import {
 } from '@/lib/image-workspace';
 import { cn } from '@/lib/utils';
 import { useImageWorkspaceStore } from '@/stores/image-workspace';
+import { useAuthStore } from '@/stores/auth';
 import type {
   DesignAsset,
   DesignGenerationQuote,
@@ -184,6 +185,7 @@ function QuoteCard({
 }
 
 export function ImageCanvas() {
+  const authenticated = useAuthStore((state) => state.isAuthenticated());
   const status = useImageWorkspaceStore((state) => state.status);
   const bootstrap = useImageWorkspaceStore((state) => state.bootstrap);
   const workspace = useImageWorkspaceStore((state) => state.workspace);
@@ -207,8 +209,8 @@ export function ImageCanvas() {
   const hasActiveTasks = tasks.some((task) => ACTIVE_TASK_STATUSES.has(task.status));
 
   useEffect(() => {
-    if (status === 'idle') void load();
-  }, [load, status]);
+    if (status === 'idle' || (status === 'auth-required' && authenticated)) void load();
+  }, [authenticated, load, status]);
 
   useEffect(() => {
     if (!hasActiveTasks || !workspace) return;