feat(push): 测试推送支持选择指定设备，默认最近登录设备

- 设备选择器显示全部设备，预选最近登录项
- sent=false && targetCount>0 时显示厂商拒绝提示
- testOffline API 新增 deviceId 参数

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tenant-platform/src/api/push.ts

@@ -81,10 +81,11 @@ export const pushAdminApi = {
     })
   },
 
-  testOffline(appKey: string, userId: string, title: string, body: string, payload?: string) {
+  testOffline(appKey: string, userId: string, title: string, body: string, payload?: string, deviceId?: string | null) {
     return client.post<{ data: TestPushResult }>('/push/admin/test-offline', {
       appKey,
       userId,
+      deviceId: deviceId ?? null,
       title,
       body,
       payload: payload ?? null,

tenant-platform/src/views/push/PushManagementView.vue

@@ -106,6 +106,17 @@
         <el-card shadow="never" style="margin-bottom:0">
           <template #header>发送测试离线推送</template>
           <el-form :model="testForm" label-width="90px" style="max-width:560px">
+            <el-form-item label="目标设备">
+              <el-select v-model="testForm.deviceId" style="width:100%" placeholder="按策略自动选择">
+                <el-option :value="null" label="按策略自动推送（平台按登录模式选取）" />
+                <el-option
+                  v-for="dev in userStatus?.devices"
+                  :key="dev.id"
+                  :value="dev.id"
+                  :label="`${dev.vendor}${dev.brand ? ' · ' + dev.brand : ''}${dev.model ? ' ' + dev.model : ''}${dev.lastLoginAt ? ' · 登录 ' + formatTime(dev.lastLoginAt) : ''}${!dev.receivePush ? ' [已关闭推送]' : ''}`"
+                />
+              </el-select>
+            </el-form-item>
             <el-form-item label="标题">
               <el-input v-model="testForm.title" placeholder="推送标题" />
             </el-form-item>
@@ -126,8 +137,12 @@
           </el-form>
           <template v-if="testResult">
             <el-alert
-              :title="testResult.sent ? `推送已发出，目标设备 ${testResult.targetCount} 台` : '无可用推送目标，未发送'"
-              :type="testResult.sent ? 'success' : 'warning'"
+              :title="testResult.sent
+                ? `推送已发出，目标设备 ${testResult.targetCount} 台`
+                : testResult.targetCount > 0
+                  ? '设备已找到但推送失败，请检查厂商凭据配置（小米 AppSecret / VIVO AppKey 等）'
+                  : '无可用推送目标，未发送'"
+              :type="testResult.sent ? 'success' : testResult.targetCount > 0 ? 'error' : 'warning'"
               :closable="false"
               show-icon
               style="margin-top:12px"
@@ -246,7 +261,7 @@ const queryUserId = ref('')
 const querying = ref(false)
 const userStatus = ref<UserPushStatus | null>(null)
 
-const testForm = reactive({ title: '', body: '', payload: '' })
+const testForm = reactive({ title: '', body: '', payload: '', deviceId: null as string | null })
 const sending = ref(false)
 const testResult = ref<TestPushResult | null>(null)
 
@@ -274,6 +289,8 @@ async function queryUser() {
   try {
     const res = await pushAdminApi.getUserStatus(appKey.value, uid)
     userStatus.value = res.data.data
+    // default to last-login device (devices are ordered by lastLoginAt DESC)
+    testForm.deviceId = res.data.data.devices[0]?.id ?? null
     logsUserId.value = uid
     logsPage.value = 1
     await loadLogs()
@@ -295,6 +312,7 @@ async function sendTestPush() {
       testForm.title,
       testForm.body,
       testForm.payload || undefined,
+      testForm.deviceId,
     )
     testResult.value = res.data.data
   } catch {