fix(userManagement): 补传添加成员 relationType 并修复删除后同步空列表报错

- 一键添加本人传 relationType=1，其他添加新增传 relationType=2
- _clearAndSync 待下发列表为空时跳过 syncMembersToDevice，避免空列表 reject

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

miniprogram/pages/addUser/addUser.ts

@@ -420,6 +420,7 @@ Page({
 
         const payload: Record<string, any> = {
             ...baseSpread,
+            ...(editId ? {} : { relationType: 2 }),
             dataType: userType === 'family' ? 1 : 0,
             parentUserId: userInfo?.userId ?? '',
             sn: targetSn,

miniprogram/pages/userManagement/userManagement.ts

@@ -391,12 +391,15 @@ Page({
 
         this.setData({ syncShow: true, syncPercent: 0, syncStatus: '正在清空并重新下发...' })
         leFuService.clearDeviceMembers()
-            .then(() => leFuService.syncMembersToDevice(syncDataList, (current, total) => {
-                this.setData({
-                    syncPercent: Math.round((current / total) * 100),
-                    syncStatus: `正在同步 ${current}/${total}...`,
+            .then(() => {
+                if (!syncDataList.length) return
+                return leFuService.syncMembersToDevice(syncDataList, (current, total) => {
+                    this.setData({
+                        syncPercent: Math.round((current / total) * 100),
+                        syncStatus: `正在同步 ${current}/${total}...`,
+                    })
                 })
-            }))
+            })
             .then(() => this._finishSync(reportUsers, '重新下发成功'))
             .catch((err: Error) => {
                 this.setData({ syncShow: false })
@@ -485,6 +488,7 @@ Page({
         if (!sn) return
 
         addSelfUser({
+            relationType: 1,
             dataType: 0,
             parentUserId: userInfo.userId,
             sn,