feat: improve login UX and add admin login lock reset

- Translate all login error messages to Chinese (network errors, HTTP
  status codes, URL validation errors)
- Add password visibility toggle (eye icon) to login form
- Add live countdown timer when login is locked, disable login button
  during cooldown, auto-clear error when countdown ends
- Add X button red hover feedback in server settings dialog
- Add LoginGuard.Unlock() method to clear Redis lock/failure keys
- Expose POST /admin-users/:id/reset-login-lock endpoint in ops API
- Add "重置登录保护" button in ops-web user management table

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/ops-web/src/views/AdminUsersView.vue

@@ -138,6 +138,18 @@
               </a-button>
             </a-tooltip>
 
+            <a-tooltip title="重置登录保护">
+              <a-popconfirm
+                title="确认清除该用户的登录锁定状态？"
+                :ok-button-props="{ loading: resetLoginLockLoadingId === record.id }"
+                @confirm="resetLoginLock(record)"
+              >
+                <a-button type="text" shape="circle" size="small" class="action-btn action-unlock">
+                  <UnlockOutlined />
+                </a-button>
+              </a-popconfirm>
+            </a-tooltip>
+
             <a-tooltip :title="record.status === 'active' ? '停用用户' : '启用用户'">
               <a-popconfirm
                 :title="record.status === 'active' ? '确认停用该用户？' : '确认启用该用户？'"
@@ -283,6 +295,7 @@ import {
   PlayCircleOutlined,
   ReloadOutlined,
   StopOutlined,
+  UnlockOutlined,
 } from '@ant-design/icons-vue'
 import type { TableColumnsType, TablePaginationConfig } from 'ant-design-vue'
 import { message } from 'ant-design-vue'
@@ -608,6 +621,20 @@ async function resetPlanUsage(row: AdminUserRow) {
   }
 }
 
+const resetLoginLockLoadingId = ref<number | null>(null)
+
+async function resetLoginLock(row: AdminUserRow) {
+  resetLoginLockLoadingId.value = row.id
+  try {
+    await http.post(`/admin-users/${row.id}/reset-login-lock`)
+    message.success('登录保护已重置，用户可立即重新登录')
+  } catch (error) {
+    if (error instanceof OpsApiError) message.error(error.detail || error.message)
+  } finally {
+    resetLoginLockLoadingId.value = null
+  }
+}
+
 const resetOpen = ref(false)
 const resetLoading = ref(false)
 const resetTarget = ref<AdminUserRow | null>(null)
@@ -806,4 +833,8 @@ onMounted(() => {
   color: #94a3b8;
   font-size: 12px;
 }
+
+.action-unlock :deep(.anticon) {
+  color: #16a34a;
+}
 </style>