refactor(frontend): 完成所有组件的内联SVG统一替换为Icon组件

- 扩展 Icon.vue 组件，新增 60+ 图标路径
  - 导航类: arrowRight, arrowLeft, arrowUp, arrowDown, chevronUp, externalLink
  - 状态类: checkCircle, xCircle, exclamationCircle, exclamationTriangle, infoCircle
  - 用户类: user, userCircle, userPlus, users
  - 文档类: document, clipboard, copy, inbox
  - 操作类: download, upload, filter, sort
  - 安全类: key, lock, shield
  - UI类: menu, calendar, home, terminal, gift, creditCard, mail
  - 数据类: chartBar, trendingUp, database, cube
  - 其他: bolt, sparkles, cloud, server, sun, moon, book 等

- 重构 56 个 Vue 组件，用 Icon 组件替换内联 SVG
  - 净减少约 2200 行代码
  - 提升代码可维护性和一致性
  - 统一图标样式和尺寸管理

frontend/src/components/common/Toast.vue

@@ -27,9 +27,10 @@
             <div class="flex items-start gap-3">
               <!-- Icon -->
               <div class="mt-0.5 flex-shrink-0">
-                <component
-                  :is="getIcon(toast.type)"
-                  :class="['h-5 w-5', getIconColor(toast.type)]"
+                <Icon
+                  :name="getToastIconName(toast.type)"
+                  size="md"
+                  :class="getIconColor(toast.type)"
                   aria-hidden="true"
                 />
               </div>
@@ -57,13 +58,7 @@
                 class="-m-1 flex-shrink-0 rounded p-1 text-gray-400 transition-colors hover:bg-gray-100 hover:text-gray-600 dark:text-gray-500 dark:hover:bg-dark-700 dark:hover:text-gray-300"
                 aria-label="Close notification"
               >
-                <svg class="h-4 w-4" fill="currentColor" viewBox="0 0 20 20">
-                  <path
-                    fill-rule="evenodd"
-                    d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z"
-                    clip-rule="evenodd"
-                  />
-                </svg>
+                <Icon name="x" size="sm" />
               </button>
             </div>
           </div>
@@ -82,77 +77,26 @@
 </template>
 
 <script setup lang="ts">
-import { computed, onMounted, onUnmounted, h } from 'vue'
+import { computed, onMounted, onUnmounted } from 'vue'
+import Icon from '@/components/icons/Icon.vue'
 import { useAppStore } from '@/stores/app'
 
 const appStore = useAppStore()
 
 const toasts = computed(() => appStore.toasts)
 
-const getIcon = (type: string) => {
-  const icons = {
-    success: () =>
-      h(
-        'svg',
-        {
-          fill: 'currentColor',
-          viewBox: '0 0 20 20'
-        },
-        [
-          h('path', {
-            'fill-rule': 'evenodd',
-            d: 'M10 18a8 8 0 100-16 8 8 0 000 16zm3.707-9.293a1 1 0 00-1.414-1.414L9 10.586 7.707 9.293a1 1 0 00-1.414 1.414l2 2a1 1 0 001.414 0l4-4z',
-            'clip-rule': 'evenodd'
-          })
-        ]
-      ),
-    error: () =>
-      h(
-        'svg',
-        {
-          fill: 'currentColor',
-          viewBox: '0 0 20 20'
-        },
-        [
-          h('path', {
-            'fill-rule': 'evenodd',
-            d: 'M10 18a8 8 0 100-16 8 8 0 000 16zM8.707 7.293a1 1 0 00-1.414 1.414L8.586 10l-1.293 1.293a1 1 0 101.414 1.414L10 11.414l1.293 1.293a1 1 0 001.414-1.414L11.414 10l1.293-1.293a1 1 0 00-1.414-1.414L10 8.586 8.707 7.293z',
-            'clip-rule': 'evenodd'
-          })
-        ]
-      ),
-    warning: () =>
-      h(
-        'svg',
-        {
-          fill: 'currentColor',
-          viewBox: '0 0 20 20'
-        },
-        [
-          h('path', {
-            'fill-rule': 'evenodd',
-            d: 'M8.257 3.099c.765-1.36 2.722-1.36 3.486 0l5.58 9.92c.75 1.334-.213 2.98-1.742 2.98H4.42c-1.53 0-2.493-1.646-1.743-2.98l5.58-9.92zM11 13a1 1 0 11-2 0 1 1 0 012 0zm-1-8a1 1 0 00-1 1v3a1 1 0 002 0V6a1 1 0 00-1-1z',
-            'clip-rule': 'evenodd'
-          })
-        ]
-      ),
-    info: () =>
-      h(
-        'svg',
-        {
-          fill: 'currentColor',
-          viewBox: '0 0 20 20'
-        },
-        [
-          h('path', {
-            'fill-rule': 'evenodd',
-            d: 'M18 10a8 8 0 11-16 0 8 8 0 0116 0zm-7-4a1 1 0 11-2 0 1 1 0 012 0zM9 9a1 1 0 000 2v3a1 1 0 001 1h1a1 1 0 100-2v-3a1 1 0 00-1-1H9z',
-            'clip-rule': 'evenodd'
-          })
-        ]
-      )
+const getToastIconName = (type: string): 'checkCircle' | 'xCircle' | 'exclamationTriangle' | 'infoCircle' => {
+  switch (type) {
+    case 'success':
+      return 'checkCircle'
+    case 'error':
+      return 'xCircle'
+    case 'warning':
+      return 'exclamationTriangle'
+    case 'info':
+    default:
+      return 'infoCircle'
   }
-  return icons[type as keyof typeof icons] || icons.info
 }
 
 const getIconColor = (type: string): string => {