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/tests/topbar-ai-mode-switch.test.mjs

@@ -0,0 +1,39 @@
+import assert from 'node:assert/strict'
+import { readFileSync } from 'node:fs'
+import test from 'node:test'
+import { fileURLToPath } from 'node:url'
+
+const topbar = readFileSync(
+  fileURLToPath(new URL('../src/components/layout/TopBar.vue', import.meta.url)),
+  'utf8'
+)
+const topbarStyles = readFileSync(
+  fileURLToPath(new URL('../src/assets/styles/components/top-bar.css', import.meta.url)),
+  'utf8'
+)
+
+test('workbench topbar places the colorful AI mode button after the company switcher', () => {
+  assert.match(topbar, /<button class="company-switcher"[\s\S]*aria-label="切换公司"[\s\S]*<\/button>\s*<button[\s\S]*class="topbar-ai-mode-toggle"/)
+  assert.match(topbar, /class="topbar-ai-mode-toggle__glyph">AI<\/span>/)
+  assert.match(topbar, /@click="toggleTopbarWorkbenchMode"/)
+  assert.match(topbar, /:aria-pressed="isTopbarAiMode"/)
+  assert.match(topbar, /:title="topbarWorkbenchModeTitle"/)
+  assert.match(topbar, /workbenchMode:\s*\{[\s\S]*type:\s*String,[\s\S]*default:\s*'traditional'/)
+  assert.doesNotMatch(topbar, /const topbarWorkbenchMode = ref/)
+  assert.match(topbar, /const isTopbarAiMode = computed\(\(\) => props\.workbenchMode === 'ai'\)/)
+  assert.match(topbar, /const topbarWorkbenchModeTitle = computed/)
+  assert.match(topbar, /const showAiModeUtilityActions = computed\(\(\) => isTopbarAiMode\.value && !isWorkbench\.value\)/)
+  assert.match(topbar, /<div v-if="showAiModeUtilityActions" class="topbar-utility-actions"/)
+  assert.match(topbar, /function toggleTopbarWorkbenchMode\(\)/)
+  assert.match(topbar, /emit\('toggleWorkbenchMode'\)/)
+})
+
+test('topbar AI mode button keeps a circular colorful text treatment', () => {
+  assert.match(topbarStyles, /\.topbar-ai-mode-toggle\s*\{[\s\S]*width:\s*38px;[\s\S]*height:\s*38px;[\s\S]*border-radius:\s*50%;/)
+  assert.match(topbarStyles, /\.topbar-ai-mode-toggle\s*\{[\s\S]*conic-gradient\(from 210deg,[\s\S]*border-box;/)
+  assert.match(topbarStyles, /\.topbar-ai-mode-toggle__glyph\s*\{[\s\S]*linear-gradient\(135deg,[\s\S]*background-clip:\s*text;[\s\S]*letter-spacing:\s*0;/)
+  assert.match(topbarStyles, /\.topbar-ai-mode-toggle:hover,[\s\S]*\.topbar-ai-mode-toggle:focus-visible\s*\{[\s\S]*transform:\s*translateY\(-1px\);/)
+  assert.match(topbarStyles, /\.topbar-utility-actions\s*\{[\s\S]*display:\s*inline-flex;[\s\S]*justify-content:\s*flex-end;/)
+  assert.match(topbarStyles, /@media \(max-width: 960px\)[\s\S]*\.topbar-ai-mode-toggle\s*\{[\s\S]*width:\s*34px;[\s\S]*height:\s*34px;/)
+  assert.match(topbarStyles, /@media \(max-width: 640px\)[\s\S]*\.topbar-ai-mode-toggle\s*\{[\s\S]*flex:\s*0 0 34px;/)
+})