feat: 会议劳务/会务材料分轨审核 + 注册页标题 + 下拉空值修复

会议材料分轨 (material_audit_stage 单轨 → labor/service 双轨):
- biz_meeting: labor_audit_stage/labor_compliance_approved + service_audit_stage/service_compliance_approved 四列替换原单轨两列
- StageDeriver: 单轨状态机(R/N/C0/C1/A) + 角色优先级选代表轨 + 会议物理态取两轨最小进度
- MeetingAuditStageEnum / 前端 meetingStage.js 镜像: 分轨推导 + 颜色跟随角色展示阶段(避免文案与颜色错位)
- BizMeetingController/ServiceImpl/AuditLog + mapper + MeetingStageScheduler 同步分轨字段
- MeetingDetail/Meetings/doctor/executor Meetings/ManagerProjectDetail/ManagerProjectsAssign/PublicityDetail 同步双轨

其它:
- 注册页 (执行单位/专家/支持单位) 加居中页标题
- DoctorDeptSelect/DoctorTitleSelect 空字符串统一 null, 避免挂载必填项飘红
- BizOrgMapper sponsor/executor options 加 status 字段
- sponsor/NewPerson 编辑态 orgName 只读

ry-vue3/src/views/portal/PublicityDetail.vue

@@ -93,7 +93,7 @@
       <!-- 右: 操作按钮 - 悬浮固定到页面最右 (按选中 tab 动态显示) -->
       <aside class="detail-actions">
         <!-- 邀请函: 立即报名 -->
-        <button v-if="activeTab === 'invitation'" class="action-btn primary signup-btn" :disabled="signing || signed" @click="onSignup">
+        <button v-if="activeTab === 'invitation' && canShowSignupBtn" class="action-btn primary signup-btn" :disabled="signing || signed" @click="onSignup">
           <svg class="btn-icon" viewBox="0 0 24 24" fill="currentColor" width="14" height="14">
             <path d="M14 2H6c-1.1 0-2 .9-2 2v16c0 1.1.9 2 2 2h12c1.1 0 2-.9 2-2V8l-6-6zm-1 7V3.5L18.5 9H13z"/>
           </svg>
@@ -217,6 +217,12 @@ const canShowExecutionBtn = computed(() => {
   if (!r) return true
   return r === 'executor'
 })
+// 立即报名 (专家参与邀请函): 仅专家 + 匿名可见; sponsor/executor/manager/admin 隐藏
+const canShowSignupBtn = computed(() => {
+  const r = userStore.user?.role || ''
+  if (!r) return true
+  return r === 'doctor'
+})
 
 const showQr = ref(false)
 const qrUrl = ref('')
@@ -380,6 +386,7 @@ async function checkSigned() {
 }
 const signing = ref(false)
 async function onSignup() {
+  if (!canShowSignupBtn.value) return  // 防御: 防止 v-if 被绕过
   if (!loggedIn.value) {
     ElMessage.warning('请先登录系统')
     router.push('/login')