feat(ui): remove in-app entity switcher, entity fixed at login

- MainLayout/ReportCenter: drop switch-entity switcher, keep read-only entity tag
- KPIList/PredictDashboard/GrowthQuality: entity selectors locked to session entity
- api/index.ts: drop switchEntity/myEntities wrappers (endpoint kept for compat)
- sidebar brand now shows logged-in entity name

(cma-remove-inapp-entity-switcher-20260914)

frontend/src/layouts/MainLayout.vue

@@ -28,12 +28,8 @@
           <span class="page-title">{{ pageTitle }}</span>
         </div>
         <div class="header-right">
-          <!-- 固定企业版（Phase C）：显示当前企业 tag 代替切换器 -->
-          <el-tag v-if="isFixedEntity()" size="small" type="primary" effect="plain" class="entity-tag">{{ currentEntityName }}</el-tag>
-          <!-- 企业切换器：仅非固定版且授权企业≥2时显示（多企业用户），固定版/单企业用户隐藏避免UI噪音 -->
-          <el-select v-else-if="entities.length >= 2" v-model="currentEntityId" @change="onEntityChange" size="small" style="width:120px;margin-right:8px;">
-            <el-option v-for="e in entities" :key="e.id" :label="e.short_name || e.name" :value="e.id" />
-          </el-select>
+          <!-- 企业只读标识（不可点）：账套由登录窗口选定，应用内无切换入口（换企业须退出重登） -->
+          <el-tag size="small" type="primary" effect="plain" class="entity-tag">{{ currentEntityName }}</el-tag>
           <el-tag size="small" :type="roleTagType">{{ roleLabel }}</el-tag>
           <el-dropdown trigger="click">
             <span class="user-info"><el-icon><User /></el-icon>{{ userName }}</span>
@@ -49,62 +45,29 @@
 </template>
 
 <script setup lang="ts">
-import { ref, computed, onMounted } from 'vue'
+import { ref, computed } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
-import { ElMessage } from 'element-plus'
-import api from '../api/index'
 import {
   User, Monitor, Document, TrendCharts, WarningFilled, Connection,
   Menu, Bell, Setting, Coin, DataAnalysis, Money, DataLine,
   DataBoard, Tools, Collection, Edit, Reading, Opportunity, PieChart,
 } from '@element-plus/icons-vue'
 import { MENU_ITEMS, ROLE_LABELS } from '../permission'
-import { isFixedEntity } from '../utils/entity'
 
 const route = useRoute()
 const router = useRouter()
 const isCollapse = ref(false)
 const mobileMenuOpen = ref(false)
 
-// 侧边栏品牌：固定企业版带企业名（如「陕西酣客 · 管理会计OS」），切换版保持原名
+// 侧边栏品牌：带当前登录企业名（如「陕西酣客 · 管理会计OS」），账套由登录窗口选定
 const logoText = computed(() => {
-  if (isFixedEntity() && currentEntityName.value) return `${currentEntityName.value} · 管理会计OS`
+  if (currentEntityName.value) return `${currentEntityName.value} · 管理会计OS`
   return '管理会计OS'
 })
 
-// ── 全局企业切换（账套模式：switch-entity 重新签发token + 整页刷新） ──
-const entities = ref<any[]>([])
-const currentEntityId = ref(Number(localStorage.getItem('cma_entity_id') || 1))
+// ── 当前企业（只读标识）：2026-09-14 需求——取消应用内企业切换，
+//    账套由登录窗口选定（localStorage.cma_entity_id 登录时写入），本页不再加载授权企业列表、不再调 switch-entity。
 const currentEntityName = ref(localStorage.getItem('cma_entity_name') || '酣客')
-async function onEntityChange(id: number) {
-  if (id === Number(localStorage.getItem('cma_entity_id'))) return
-  try {
-    const r: any = await api.post('/auth/switch-entity', {
-      entity_id: id,
-      from_entity_id: Number(localStorage.getItem('cma_entity_id') || 1),
-    })
-    localStorage.setItem('cma_token', r.token)
-    localStorage.setItem('cma_entity_id', String(r.entity_id))
-    localStorage.setItem('cma_entity_name', r.entity_short_name || r.entity_name || '')
-    // 多租户联动：通知后端记录当前tenant（供项目Bot A2A分发）
-    try {
-      api.post('/tenant/switch', { entity_id: r.entity_id, source: 'cma-frontend' })
-    } catch (_) {}
-    location.reload()
-  } catch (e: any) {
-    currentEntityId.value = Number(localStorage.getItem('cma_entity_id') || 1)
-    const msg = e?.response?.data?.detail || '切换失败'
-    ElMessage.error(msg)
-  }
-}
-onMounted(async () => {
-  // 账套模式：切换器只显示当前用户被授权的企业；固定企业版无切换需求，跳过列表加载
-  if (isFixedEntity()) return
-  try {
-    const r: any = await api.get('/auth/my-entities')
-    entities.value = r.data || r || []
-  } catch (_) {}
-})
 
 // 图标名称 → 组件实例映射
 const iconMap: Record<string, any> = {