ci: use Docker agent for yarn build stage on Windows Jenkins

Run yarn install/build inside node:22-alpine Linux container via Docker
Pipeline plugin; Docker/SSH deploy stages remain on native agent.

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

Jenkinsfile

@@ -1,5 +1,5 @@
 pipeline {
-  agent any
+  agent none
 
   parameters {
     choice(name: 'APP', choices: ['tenant-platform', 'ops-platform'], description: '要构建的 Web 应用')
@@ -18,22 +18,36 @@ pipeline {
 
   stages {
     stage('Checkout') {
-      steps { checkout scm }
+      agent any
+      steps {
+        checkout scm
+        stash name: 'source', includes: '**/*'
+      }
     }
 
     stage('Install & Build') {
+      agent {
+        docker {
+          image 'node:22-alpine'
+          args '-v yarn-cache:/root/.yarn'
+        }
+      }
       steps {
+        unstash 'source'
         dir("${params.APP}") {
           sh '''
             yarn install --frozen-lockfile
             yarn build
           '''
         }
+        stash name: 'dist', includes: "${params.APP}/dist/**,${params.APP}/Dockerfile"
       }
     }
 
     stage('Docker Build & Push') {
+      agent any
       steps {
+        unstash 'dist'
         withCredentials([string(credentialsId: 'ACR_PASSWORD', variable: 'ACR_PASS')]) {
           script {
             def imageName = "${ACR_REGISTRY}/${ACR_NAMESPACE}/web-${params.APP}:${params.IMAGE_TAG}"
@@ -49,6 +63,7 @@ pipeline {
     }
 
     stage('Deploy to Production') {
+      agent any
       when { expression { return params.DEPLOY } }
       steps {
         withCredentials([sshUserPrivateKey(credentialsId: 'PROD_SSH_KEY', keyFileVariable: 'SSH_KEY')]) {