fix: Add missing maven-wrapper.jar for Docker builds

- Download maven-wrapper.jar from Maven Central Repository
- Update .gitignore to allow maven-wrapper.jar to be committed
- This fixes 'Could not find or load main class org.apache.maven.wrapper.MavenWrapperMain' error
- Ensures Maven Wrapper works properly in CI/CD and Docker environments
- Enables builds without pre-installed Maven

.gitignore

@@ -34,7 +34,8 @@ release.properties
 dependency-reduced-pom.xml
 buildNumber.properties
 .mvn/timing.properties
-.mvn/wrapper/maven-wrapper.jar
+# Note: maven-wrapper.jar should be committed to enable builds without Maven pre-installed
+# .mvn/wrapper/maven-wrapper.jar
 
 # Eclipse
 .metadata