Added Jenkinsfile for CI pipeline

Jenkinsfile

@@ -0,0 +1,55 @@
+pipeline {
+    agent any
+
+    triggers {
+        cron('H/3 * * * 4') // Runs every 3 minutes on Thursdays
+    }
+
+    tools {
+        maven 'Maven 3'
+        jdk 'JDK 11'
+    }
+
+    stages {
+        stage('Checkout') {
+            steps {
+                git 'https://github.com/girisujan2001/spring-petclinic.git'
+            }
+        }
+
+        stage('Build') {
+            steps {
+                sh 'mvn clean package'
+            }
+        }
+
+        stage('Test & Code Coverage') {
+            steps {
+                sh 'mvn test'
+                sh 'mvn jacoco:report'
+            }
+        }
+
+        stage('Archive Artifacts') {
+            steps {
+                archiveArtifacts artifacts: 'target/*.jar', fingerprint: true
+            }
+        }
+
+        stage('Publish Jacoco Report') {
+            steps {
+                jacoco execPattern: '**/target/jacoco.exec', classPattern: '**/target/classes', sourcePattern: '**/src/main/java'
+            }
+        }
+    }
+
+    post {
+        success {
+            echo 'Pipeline executed successfully!'
+        }
+        failure {
+            echo 'Pipeline failed!'
+        }
+    }
+}
+