Jenkinsfile: Build Docker image locally when not present

- Add Docker Image stage that checks if image exists and builds if needed
- Fix nested stages structure in Build and Test stage
- Docker image built on Jenkins host instead of pulling from registry
- Resolves 'pull access denied' error when image not in registry

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Entire-Checkpoint: 443ea4c1ce1c

Jenkinsfile

@@ -1,10 +1,5 @@
 pipeline {
-  agent {
-    docker {
-      image 'lifemaps/ci-cpp:latest'
-      reuseNode true
-    }
-  }
+  agent none
 
   options {
     timestamps()
@@ -19,14 +14,38 @@ pipeline {
     QT_QPA_PLATFORM = "offscreen"
     LANG = "C.UTF-8"
     LC_ALL = "C.UTF-8"
+    DOCKER_IMAGE = "lifemaps/ci-cpp:latest"
   }
 
+  stages {
+    stage('Docker Image') {
+      agent { label 'any' }
+      steps {
+        script {
+          echo "Checking if Docker image exists locally..."
+          def imageExists = sh(script: "docker inspect ${DOCKER_IMAGE} >/dev/null 2>&1", returnStatus: true) == 0
+          if (!imageExists) {
+            echo "Docker image not found. Building from ci/Dockerfile.ci..."
+            sh 'docker build -t ${DOCKER_IMAGE} -f ci/Dockerfile.ci .'
+          } else {
+            echo "Docker image ${DOCKER_IMAGE} found locally."
+          }
+        }
+      }
+    }
+
+    stage('Build and Test') {
+      agent {
+        docker {
+          image 'lifemaps/ci-cpp:latest'
+          reuseNode true
+        }
+      }
       stages {
         stage('Cleanup') {
           steps {
             script {
               echo "Cleaning workspace to avoid corruption issues..."
-          // Use shell command with chmod to handle permission issues
               sh '''
                 if [ -d "${WORKSPACE}/${BUILD_DIR}" ]; then
                   echo "Removing build directory with permission fix..."
@@ -124,12 +143,13 @@ pipeline {
           }
         }
       }
+    }
+  }
 
   post {
     always {
       script {
         if (getContext(hudson.FilePath)) {
-          // Use shell command with chmod to handle permission issues
           sh '''
             if [ -d "${WORKSPACE}/${BUILD_DIR}" ]; then
               echo "Final cleanup: Removing build directory..."