Fix Maven compiler plugin: add missing lombok.version property

The maven-compiler-plugin configuration referenced ${lombok.version}
but the property was not defined, causing build failures.

Added lombok.version=1.18.30 to match Spring Boot's managed version.

Author: akovari

pom.xml

@@ -43,6 +43,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <spring-boot.version>3.2.0</spring-boot.version>
         <junit.version>5.10.1</junit.version>
+        <lombok.version>1.18.30</lombok.version>
     </properties>
 
     <dependencyManagement>