feat: 任务全景搜索框增加一键清除(×)按钮

frontend/src/pages/admin/AdminTasksPage.tsx

@@ -264,8 +264,17 @@ export default function AdminTasksPage() {
               value={keyword}
               onChange={(e) => setKeyword(e.target.value)}
               placeholder="搜索产品身份证、订单号、规格型号..."
-              className="w-full rounded-lg border border-gray-200 py-2.5 pl-9 pr-3 text-sm focus:border-blue-400 focus:outline-none focus:ring-2 focus:ring-blue-100"
+              className="w-full rounded-lg border border-gray-200 py-2.5 pl-9 pr-8 text-sm focus:border-blue-400 focus:outline-none focus:ring-2 focus:ring-blue-100"
             />
+            {keyword && (
+              <button
+                type="button"
+                onClick={() => { setKeyword(""); loadProducts(""); }}
+                className="absolute right-2 top-1/2 -translate-y-1/2 rounded-full p-0.5 text-gray-400 hover:text-gray-600 hover:bg-gray-100"
+              >
+                <X className="h-4 w-4" />
+              </button>
+            )}
           </div>
           <button
             type="submit"