feat: 移除侧边栏中的上游网址快捷入口，并在上游管理列表各条记录操作列增加官网跳转按钮

frontend/src/views/Upstreams.vue

@@ -91,9 +91,10 @@
           </template>
         </el-table-column>
 
-        <el-table-column label="操作" width="280">
+        <el-table-column label="操作" width="320">
           <template #default="{ row }">
             <div class="action-row">
+              <el-button size="small" text :disabled="!row.base_url" @click="openOfficialSite(row)" title="在新标签页中打开上游官网">官网</el-button>
               <el-button size="small" text @click="openEdit(row)" title="编辑上游配置（认证、接口、余额等）">编辑</el-button>
               <el-button size="small" text @click="testUpstream(row)" :loading="row._testing" title="仅验证连通性：登录 + 拉取分组列表，不写快照、不触发通知">测试连接</el-button>
               <el-button size="small" text @click="checkNow(row)" :loading="row._checking" title="完整同步：拉取倍率 → 生成快照 → 对比变化 → 触发 Webhook → 同步 Key">立即同步</el-button>
@@ -977,6 +978,11 @@ function openCreate() {
   drawerVisible.value = true
 }
 
+function openOfficialSite(row: UpstreamData) {
+  if (!row.base_url) return
+  window.open(row.base_url, '_blank', 'noopener,noreferrer')
+}
+
 function openEdit(row: UpstreamData) {
   editingId.value = row.id
   quickPlatform.value = inferPlatform(row)