Run pipeline on swarm-labeled inbound agent

Jenkinsfile

@@ -1,5 +1,5 @@
 pipeline {
-    agent any
+    agent { label 'swarm' }
 
     options {
         buildDiscarder(logRotator(numToKeepStr: '20'))
@@ -14,6 +14,15 @@ pipeline {
             }
         }
 
+        stage('Swarm Agent Check') {
+            steps {
+                sh 'hostname'
+                sh 'id'
+                sh 'docker version --format "{{.Server.Version}}"'
+                sh 'docker service ls --format "{{.Name}} {{.Replicas}}"'
+            }
+        }
+
         stage('Service Reachability') {
             steps {
                 sh 'curl -fsS https://gitea.derryle.com/user/login > /dev/null'