fix(frontend): health-plan-summary 成员列表 wx:key 表达式改用方法调用

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

cfc-frontend/pages/health/health-plan-summary.vue

@@ -25,7 +25,7 @@
       <view class="member-list">
         <view
           v-for="(m, idx) in executors"
-          :key="m.memberId || idx"
+          :key="getMemberKey(m, idx)"
           class="member-card"
           :class="{ active: selectedMemberIds.indexOf(m.memberId) >= 0 }"
           @click="toggleMember(m.memberId)"
@@ -196,6 +196,7 @@ export default {
     this.loadHealthContext()
   },
   methods: {
+    getMemberKey: function(m, idx) { return m.memberId || idx },
     loadExecutors: function() {
       var self = this
       getFamilyMembers().then(function(res) {