feat(admin): 添加 LinuxDO OAuth 回调地址快速设置按钮

- 在设置页面添加"使用当前站点生成并复制"按钮
- 自动填充回调地址并复制到剪贴板
- 添加中英文国际化支持

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/i18n/locales/en.ts

@@ -1782,7 +1782,9 @@ export default {
         redirectUrl: 'Redirect URL',
         redirectUrlPlaceholder: 'https://your-domain.com/api/v1/auth/oauth/linuxdo/callback',
         redirectUrlHint:
-          'Must match the redirect URL configured in Connect.Linux.Do (must be an absolute http(s) URL)'
+          'Must match the redirect URL configured in Connect.Linux.Do (must be an absolute http(s) URL)',
+        quickSetCopy: 'Generate & Copy (current site)',
+        redirectUrlSetAndCopied: 'Redirect URL generated and copied to clipboard'
       },
       defaults: {
         title: 'Default User Settings',

frontend/src/i18n/locales/zh.ts

@@ -1926,7 +1926,9 @@ export default {
         clientSecretConfiguredHint: '密钥已配置，留空以保留当前值。',
         redirectUrl: '回调地址（Redirect URL）',
         redirectUrlPlaceholder: 'https://your-domain.com/api/v1/auth/oauth/linuxdo/callback',
-        redirectUrlHint: '需与 Connect.Linux.Do 中配置的回调地址一致（必须是 http(s) 完整 URL）'
+        redirectUrlHint: '需与 Connect.Linux.Do 中配置的回调地址一致（必须是 http(s) 完整 URL）',
+        quickSetCopy: '使用当前站点生成并复制',
+        redirectUrlSetAndCopied: '已使用当前站点生成回调地址并复制到剪贴板'
       },
       defaults: {
         title: '用户默认设置',

frontend/src/views/admin/SettingsView.vue

@@ -337,6 +337,21 @@
                     class="input font-mono text-sm"
                     :placeholder="t('admin.settings.linuxdo.redirectUrlPlaceholder')"
                   />
+                  <div class="mt-2 flex flex-col gap-2 sm:flex-row sm:items-center sm:gap-3">
+                    <button
+                      type="button"
+                      class="btn btn-secondary btn-sm w-fit"
+                      @click="setAndCopyLinuxdoRedirectUrl"
+                    >
+                      {{ t('admin.settings.linuxdo.quickSetCopy') }}
+                    </button>
+                    <code
+                      v-if="linuxdoRedirectUrlSuggestion"
+                      class="select-all break-all rounded bg-gray-50 px-2 py-1 font-mono text-xs text-gray-600 dark:bg-dark-800 dark:text-gray-300"
+                    >
+                      {{ linuxdoRedirectUrlSuggestion }}
+                    </code>
+                  </div>
                   <p class="mt-1.5 text-xs text-gray-500 dark:text-gray-400">
                     {{ t('admin.settings.linuxdo.redirectUrlHint') }}
                   </p>
@@ -777,17 +792,19 @@
 </template>
 
 <script setup lang="ts">
-import { ref, reactive, onMounted } from 'vue'
+import { ref, reactive, computed, onMounted } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { adminAPI } from '@/api'
 import type { SystemSettings, UpdateSettingsRequest } from '@/api/admin/settings'
 import AppLayout from '@/components/layout/AppLayout.vue'
 import Icon from '@/components/icons/Icon.vue'
 import Toggle from '@/components/common/Toggle.vue'
+import { useClipboard } from '@/composables/useClipboard'
 import { useAppStore } from '@/stores'
 
 const { t } = useI18n()
 const appStore = useAppStore()
+const { copyToClipboard } = useClipboard()
 
 const loading = ref(true)
 const saving = ref(false)
@@ -844,6 +861,21 @@ const form = reactive<SettingsForm>({
   identity_patch_prompt: ''
 })
 
+const linuxdoRedirectUrlSuggestion = computed(() => {
+  if (typeof window === 'undefined') return ''
+  const origin =
+    window.location.origin || `${window.location.protocol}//${window.location.host}`
+  return `${origin}/api/v1/auth/oauth/linuxdo/callback`
+})
+
+async function setAndCopyLinuxdoRedirectUrl() {
+  const url = linuxdoRedirectUrlSuggestion.value
+  if (!url) return
+
+  form.linuxdo_connect_redirect_url = url
+  await copyToClipboard(url, t('admin.settings.linuxdo.redirectUrlSetAndCopied'))
+}
+
 function handleLogoUpload(event: Event) {
   const input = event.target as HTMLInputElement
   const file = input.files?.[0]