feat: add 529 overload cooldown toggle and duration settings in admin gateway page

Move 529 overload cooldown configuration from config file to admin
settings UI. Adds an enable/disable toggle and configurable cooldown
duration (1-120 min) under /admin/settings gateway tab, stored as
JSON in the settings table.

When disabled, 529 errors are logged but accounts are no longer
paused from scheduling. Falls back to config file value when DB
is unreachable or settingService is nil.

frontend/src/api/admin/settings.ts

@@ -242,6 +242,33 @@ export async function deleteAdminApiKey(): Promise<{ message: string }> {
   return data
 }
 
+// ==================== Overload Cooldown Settings ====================
+
+/**
+ * Overload cooldown settings interface (529 handling)
+ */
+export interface OverloadCooldownSettings {
+  enabled: boolean
+  cooldown_minutes: number
+}
+
+export async function getOverloadCooldownSettings(): Promise<OverloadCooldownSettings> {
+  const { data } = await apiClient.get<OverloadCooldownSettings>('/admin/settings/overload-cooldown')
+  return data
+}
+
+export async function updateOverloadCooldownSettings(
+  settings: OverloadCooldownSettings
+): Promise<OverloadCooldownSettings> {
+  const { data } = await apiClient.put<OverloadCooldownSettings>(
+    '/admin/settings/overload-cooldown',
+    settings
+  )
+  return data
+}
+
+// ==================== Stream Timeout Settings ====================
+
 /**
  * Stream timeout settings interface
  */
@@ -499,6 +526,8 @@ export const settingsAPI = {
   getAdminApiKey,
   regenerateAdminApiKey,
   deleteAdminApiKey,
+  getOverloadCooldownSettings,
+  updateOverloadCooldownSettings,
   getStreamTimeoutSettings,
   updateStreamTimeoutSettings,
   getRectifierSettings,

frontend/src/i18n/locales/en.ts

@@ -4362,6 +4362,16 @@ export default {
           testFailed: 'Google Drive storage test failed'
         }
       },
+      overloadCooldown: {
+        title: '529 Overload Cooldown',
+        description: 'Configure account scheduling pause strategy when upstream returns 529 (overloaded)',
+        enabled: 'Enable Overload Cooldown',
+        enabledHint: 'Pause account scheduling on 529 errors, auto-recover after cooldown',
+        cooldownMinutes: 'Cooldown Duration (minutes)',
+        cooldownMinutesHint: 'Duration to pause account scheduling (1-120 minutes)',
+        saved: 'Overload cooldown settings saved',
+        saveFailed: 'Failed to save overload cooldown settings'
+      },
       streamTimeout: {
         title: 'Stream Timeout Handling',
         description: 'Configure account handling strategy when upstream response times out',

frontend/src/i18n/locales/zh.ts

@@ -4527,6 +4527,16 @@ export default {
           testFailed: 'Google Drive 存储测试失败'
         }
       },
+      overloadCooldown: {
+        title: '529 过载冷却',
+        description: '配置上游返回 529（过载）时的账号调度暂停策略',
+        enabled: '启用过载冷却',
+        enabledHint: '收到 529 错误时暂停该账号的调度，冷却后自动恢复',
+        cooldownMinutes: '冷却时长（分钟）',
+        cooldownMinutesHint: '账号暂停调度的持续时间（1-120 分钟）',
+        saved: '过载冷却设置保存成功',
+        saveFailed: '保存过载冷却设置失败'
+      },
       streamTimeout: {
         title: '流超时处理',
         description: '配置上游响应超时时的账户处理策略，避免问题账户持续被选中',

frontend/src/views/admin/SettingsView.vue

@@ -168,8 +168,93 @@
         </div>
         </div><!-- /Tab: Security — Admin API Key -->
 
-        <!-- Tab: Gateway — Stream Timeout -->
+        <!-- Tab: Gateway -->
         <div v-show="activeTab === 'gateway'" class="space-y-6">
+
+        <!-- Overload Cooldown (529) Settings -->
+        <div class="card">
+          <div class="border-b border-gray-100 px-6 py-4 dark:border-dark-700">
+            <h2 class="text-lg font-semibold text-gray-900 dark:text-white">
+              {{ t('admin.settings.overloadCooldown.title') }}
+            </h2>
+            <p class="mt-1 text-sm text-gray-500 dark:text-gray-400">
+              {{ t('admin.settings.overloadCooldown.description') }}
+            </p>
+          </div>
+          <div class="space-y-5 p-6">
+            <div v-if="overloadCooldownLoading" class="flex items-center gap-2 text-gray-500">
+              <div class="h-4 w-4 animate-spin rounded-full border-b-2 border-primary-600"></div>
+              {{ t('common.loading') }}
+            </div>
+
+            <template v-else>
+              <div class="flex items-center justify-between">
+                <div>
+                  <label class="font-medium text-gray-900 dark:text-white">{{
+                    t('admin.settings.overloadCooldown.enabled')
+                  }}</label>
+                  <p class="text-sm text-gray-500 dark:text-gray-400">
+                    {{ t('admin.settings.overloadCooldown.enabledHint') }}
+                  </p>
+                </div>
+                <Toggle v-model="overloadCooldownForm.enabled" />
+              </div>
+
+              <div
+                v-if="overloadCooldownForm.enabled"
+                class="space-y-4 border-t border-gray-100 pt-4 dark:border-dark-700"
+              >
+                <div>
+                  <label class="mb-2 block text-sm font-medium text-gray-700 dark:text-gray-300">
+                    {{ t('admin.settings.overloadCooldown.cooldownMinutes') }}
+                  </label>
+                  <input
+                    v-model.number="overloadCooldownForm.cooldown_minutes"
+                    type="number"
+                    min="1"
+                    max="120"
+                    class="input w-32"
+                  />
+                  <p class="mt-1.5 text-xs text-gray-500 dark:text-gray-400">
+                    {{ t('admin.settings.overloadCooldown.cooldownMinutesHint') }}
+                  </p>
+                </div>
+              </div>
+
+              <div class="flex justify-end border-t border-gray-100 pt-4 dark:border-dark-700">
+                <button
+                  type="button"
+                  @click="saveOverloadCooldownSettings"
+                  :disabled="overloadCooldownSaving"
+                  class="btn btn-primary btn-sm"
+                >
+                  <svg
+                    v-if="overloadCooldownSaving"
+                    class="mr-1 h-4 w-4 animate-spin"
+                    fill="none"
+                    viewBox="0 0 24 24"
+                  >
+                    <circle
+                      class="opacity-25"
+                      cx="12"
+                      cy="12"
+                      r="10"
+                      stroke="currentColor"
+                      stroke-width="4"
+                    ></circle>
+                    <path
+                      class="opacity-75"
+                      fill="currentColor"
+                      d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"
+                    ></path>
+                  </svg>
+                  {{ overloadCooldownSaving ? t('common.saving') : t('common.save') }}
+                </button>
+              </div>
+            </template>
+          </div>
+        </div>
+
         <!-- Stream Timeout Settings -->
         <div class="card">
           <div class="border-b border-gray-100 px-6 py-4 dark:border-dark-700">
@@ -1765,6 +1850,14 @@ const adminApiKeyOperating = ref(false)
 const newAdminApiKey = ref('')
 const subscriptionGroups = ref<AdminGroup[]>([])
 
+// Overload Cooldown (529) 状态
+const overloadCooldownLoading = ref(true)
+const overloadCooldownSaving = ref(false)
+const overloadCooldownForm = reactive({
+  enabled: true,
+  cooldown_minutes: 10
+})
+
 // Stream Timeout 状态
 const streamTimeoutLoading = ref(true)
 const streamTimeoutSaving = ref(false)
@@ -2274,6 +2367,37 @@ function copyNewKey() {
     })
 }
 
+// Overload Cooldown 方法
+async function loadOverloadCooldownSettings() {
+  overloadCooldownLoading.value = true
+  try {
+    const settings = await adminAPI.settings.getOverloadCooldownSettings()
+    Object.assign(overloadCooldownForm, settings)
+  } catch (error: any) {
+    console.error('Failed to load overload cooldown settings:', error)
+  } finally {
+    overloadCooldownLoading.value = false
+  }
+}
+
+async function saveOverloadCooldownSettings() {
+  overloadCooldownSaving.value = true
+  try {
+    const updated = await adminAPI.settings.updateOverloadCooldownSettings({
+      enabled: overloadCooldownForm.enabled,
+      cooldown_minutes: overloadCooldownForm.cooldown_minutes
+    })
+    Object.assign(overloadCooldownForm, updated)
+    appStore.showSuccess(t('admin.settings.overloadCooldown.saved'))
+  } catch (error: any) {
+    appStore.showError(
+      t('admin.settings.overloadCooldown.saveFailed') + ': ' + (error.message || t('common.unknownError'))
+    )
+  } finally {
+    overloadCooldownSaving.value = false
+  }
+}
+
 // Stream Timeout 方法
 async function loadStreamTimeoutSettings() {
   streamTimeoutLoading.value = true
@@ -2396,6 +2520,7 @@ onMounted(() => {
   loadSettings()
   loadSubscriptionGroups()
   loadAdminApiKey()
+  loadOverloadCooldownSettings()
   loadStreamTimeoutSettings()
   loadRectifierSettings()
   loadBetaPolicySettings()