feat(web): 工作台 AI 模式与差旅/风险建议交互优化

- 新增 PersonalWorkbenchAiMode 组件、AI 侧边栏与 orb 机器人视觉资源
- 新增 aiApplicationDraftModel / aiExpenseDraftModel / aiWorkbenchConversationStore
  及业务准入 aiSidebarBusinessAccess，支撑 AI 模式下的申请与报销草稿
- 顶栏、侧边栏、工作台样式重构，适配 AI 模式切换与响应式布局
- 同步 steward plan/off_topic、差旅报销引导流、风险建议卡片等测试

web/src/assets/styles/views/personal-workbench-view.css

@@ -0,0 +1,40 @@
+.workbench-mode-fade-enter-active,
+.workbench-mode-fade-leave-active {
+  transition:
+    opacity 220ms var(--ease, cubic-bezier(0.2, 0.8, 0.2, 1)),
+    transform 220ms var(--ease, cubic-bezier(0.2, 0.8, 0.2, 1)),
+    filter 220ms var(--ease, cubic-bezier(0.2, 0.8, 0.2, 1));
+  transform-origin: 50% 24px;
+  will-change: opacity, transform, filter;
+}
+
+.workbench-mode-fade-enter-from,
+.workbench-mode-fade-leave-to {
+  opacity: 0;
+  transform: translateY(10px) scale(0.992);
+  filter: blur(2px);
+}
+
+.workbench-mode-fade-enter-to,
+.workbench-mode-fade-leave-from {
+  opacity: 1;
+  transform: translateY(0) scale(1);
+  filter: blur(0);
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .workbench-mode-fade-enter-active,
+  .workbench-mode-fade-leave-active {
+    transition: none;
+    will-change: auto;
+  }
+
+  .workbench-mode-fade-enter-from,
+  .workbench-mode-fade-leave-to,
+  .workbench-mode-fade-enter-to,
+  .workbench-mode-fade-leave-from {
+    opacity: 1;
+    transform: none;
+    filter: none;
+  }
+}