fix(admin): copy buttons dead on HTTP origin — execCommand fallback

navigator.clipboard 仅安全上下文（HTTPS/localhost）可用，测试服务器经
http://IP:32005 访问时为 undefined，四处复制按钮（公开令牌/分享链接/
嵌入代码/重置密码）点击即抛 TypeError 且无提示。统一 utils/clipboard
copyText：API 优先、失败降级隐藏 textarea + execCommand。

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

apps/admin/src/views/albums/detail/AlbumShareCard.vue

@@ -53,6 +53,7 @@
     viewerBaseFromEnv,
     type QrDraw
   } from '@/utils/albums/shareLink'
+  import { copyText } from '@/utils/clipboard'
 
   const props = defineProps<{
     album: Api.Album.Detail
@@ -104,8 +105,11 @@
   )
 
   async function copyLink(): Promise<void> {
-    await navigator.clipboard.writeText(viewerUrl.value)
-    ElMessage.success(t('albumsManage.list.copied'))
+    if (await copyText(viewerUrl.value)) {
+      ElMessage.success(t('albumsManage.list.copied'))
+    } else {
+      ElMessage.error(t('setting.actions.copyFailed'))
+    }
   }
 </script>
 

apps/admin/src/views/system/embed-slots/EmbedCodeDialog.vue

@@ -61,6 +61,7 @@
   import { useI18n } from 'vue-i18n'
   import { ElMessage } from 'element-plus'
   import { buildEmbedSnippet, embedOriginFromEnv } from '@/utils/system/embedSlots'
+  import { copyText } from '@/utils/clipboard'
 
   const props = defineProps<{
     /** 目标展示位（publicToken 拼入 data-slot；settings 生成显式 data-* 覆盖） */
@@ -81,7 +82,10 @@
   }
 
   async function copySnippet(): Promise<void> {
-    await navigator.clipboard.writeText(snippet.value)
-    ElMessage.success(t('embedSlotsManage.code.copied'))
+    if (await copyText(snippet.value)) {
+      ElMessage.success(t('embedSlotsManage.code.copied'))
+    } else {
+      ElMessage.error(t('setting.actions.copyFailed'))
+    }
   }
 </script>

apps/admin/src/views/system/users/ResetPasswordDialog.vue

@@ -91,6 +91,7 @@
   import { useI18n } from 'vue-i18n'
   import { ElMessage } from 'element-plus'
   import { useResetPassword } from './composables/useResetPassword'
+  import { copyText } from '@/utils/clipboard'
   import type { ResetPasswordMode } from '@/utils/system/userAdmin'
 
   const props = defineProps<{
@@ -129,7 +130,10 @@
   }
 
   async function copyPassword(): Promise<void> {
-    await navigator.clipboard.writeText(flow.password.value)
-    ElMessage.success(t('usersManage.reset.copied'))
+    if (await copyText(flow.password.value)) {
+      ElMessage.success(t('usersManage.reset.copied'))
+    } else {
+      ElMessage.error(t('setting.actions.copyFailed'))
+    }
   }
 </script>