refactor(admin): tokenize 语义色并补暗黑模式变量覆盖

将 admin 8 文件 ~50 处 raw red/green/yellow/amber/blue 类替换为语义 token
（error/success/warning/info），使其错误/成功/警告框在暗黑模式正确反色。

- tailwind.config.js: error 补 text 子键（原缺，text-error 暗黑底仅 3.3:1 不达 AA）
- globals.css: 新增 --color-error-text；html[data-theme='dark'] 补四语义色的
  *-bg（深色底）与 *-text（浅色，暗底达 AA）覆盖，原暗黑块完全漏掉这些变量
- 映射纪律：语义框 bg-<c>-bg border border-border-secondary text-<c>-text；
  危险按钮 bg-error/bg-success hover:bg-*-hover text-white；字段校验 border-error

验证：type-check 0 errors；lint 0 errors；单测 1624 passed；视觉回归 22 passed；
Playwright 实测 8 变量 light/dark 翻转 + 真实登录错误框背景反色确认。

Co-Authored-By: 阿睿 <workbuddy@tencent.com>

src/app/admin/notifications/page.tsx

@@ -38,16 +38,16 @@ const NOTIFICATION_TYPE_LABELS: Record<string, string> = {
 };
 
 const NOTIFICATION_TYPE_ICONS: Record<string, React.ReactNode> = {
-  review_pending: <AlertCircle className="w-4 h-4 text-amber-500" />,
-  review_approved: <CheckCircle className="w-4 h-4 text-green-500" />,
-  review_rejected: <XCircle className="w-4 h-4 text-red-500" />,
+  review_pending: <AlertCircle className="w-4 h-4 text-warning-text" />,
+  review_approved: <CheckCircle className="w-4 h-4 text-success-text" />,
+  review_rejected: <XCircle className="w-4 h-4 text-error-text" />,
   item_archived: <Archive className="w-4 h-4 text-text-muted" />,
 };
 
 const NOTIFICATION_TYPE_COLORS: Record<string, string> = {
-  review_pending: 'bg-amber-50 border-amber-200',
-  review_approved: 'bg-green-50 border-green-200',
-  review_rejected: 'bg-red-50 border-red-200',
+  review_pending: 'bg-warning-bg border-border-secondary',
+  review_approved: 'bg-success-bg border-border-secondary',
+  review_rejected: 'bg-error-bg border-border-secondary',
   item_archived: 'bg-bg-secondary border-border-primary',
 };
 
@@ -156,7 +156,7 @@ export default function NotificationsPage() {
           <p className="text-sm text-text-muted mt-1">
             共 {total} 条通知
             {unreadCount > 0 && (
-              <span className="ml-2 inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-red-100 text-red-700">
+              <span className="ml-2 inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-error-bg text-error-text">
                 {unreadCount} 条未读
               </span>
             )}
@@ -194,7 +194,7 @@ export default function NotificationsPage() {
       </div>
 
       {error && (
-        <div className="p-4 bg-red-50 border border-red-200 rounded-lg text-sm text-red-600">
+        <div className="p-4 bg-error-bg border border-border-secondary rounded-lg text-sm text-error-text">
           {error}
         </div>
       )}
@@ -223,12 +223,12 @@ export default function NotificationsPage() {
               className={`relative flex items-start gap-4 p-4 rounded-lg border transition-colors ${
                 item.read
                   ? 'bg-bg-primary border-border-light'
-                  : NOTIFICATION_TYPE_COLORS[item.type] || 'bg-blue-50 border-blue-200'
+                  : NOTIFICATION_TYPE_COLORS[item.type] || 'bg-info-bg border-border-secondary'
               }`}
             >
               {/* Unread indicator */}
               {!item.read && (
-                <div className="absolute top-4 left-4 w-2 h-2 rounded-full bg-blue-500" />
+                <div className="absolute top-4 left-4 w-2 h-2 rounded-full bg-info" />
               )}
 
               {/* Type icon */}
@@ -278,7 +278,7 @@ export default function NotificationsPage() {
                   {item.relatedItemId && item.relatedModelCode && (
                     <button
                       onClick={() => handleViewRelated(item)}
-                      className="text-xs text-blue-600 hover:text-blue-800 flex items-center gap-1"
+                      className="text-xs text-info-text hover:text-info flex items-center gap-1"
                     >
                       <ExternalLink className="w-3 h-3" />
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