feat: page config upload button for normal sites, add cloud upload endpoint

- SitePagesController: add PUT /admin/site-pages/{siteId}/upload for uploading normal site pages to cloud storage

- SitePages.vue: show upload button for both default templates and normal sites

web/src/views/SitePages.vue

@@ -46,7 +46,7 @@
       <h2 style="margin:0">编辑: {{ editSiteId }}</h2>
       <div style="display:flex;gap:8px">
         <el-button size="small" type="primary" @click="savePages" :loading="saving">保存</el-button>
-        <el-button v-if="isDefaultEditor" size="small" @click="uploadPages" :loading="uploading">上传</el-button>
+        <el-button size="small" @click="uploadPages" :loading="uploading">上传</el-button>
         <el-button size="small" type="danger" @click="deletePages" :loading="deleting">删除</el-button>
         <el-button size="small" @click="editSiteId=''">返回列表</el-button>
       </div>
@@ -222,8 +222,12 @@ const deletePages = async () => {
 const uploadPages = async () => {
   uploading.value = true
   try {
-    const type = editSiteId.value.replace('default:','')
-    await api.raw.put('/admin/default-pages/'+type+'/upload', { entries: parsed.value })
+    if (editSiteId.value.startsWith('default:')) {
+      const type = editSiteId.value.replace('default:','')
+      await api.raw.put('/admin/default-pages/'+type+'/upload', { entries: parsed.value })
+    } else {
+      await api.raw.put('/admin/site-pages/'+editSiteId.value+'/upload', { entries: parsed.value, authType: authType.value })
+    }
     ElMessage.success('已上传到云存储')
   } catch { ElMessage.error('上传失败') }
   finally { uploading.value = false }