[Feature Request]: Support Exporting Web Server to .war File for Easier Integration with Keycloak

### What would you like to happen?

## Description
Currently, the Apache Hop project utilizes an embedded Jetty server, which requires programmatic configuration for web server functionalities, including security handling with Keycloak. This setup poses challenges in environments that prefer or exclusively support WAR deployments, common in enterprise setups that utilize application servers like Tomcat or WildFly.

## Feature Request
I propose adding support to export the Hop Web Server as a .war file. This change would simplify deploying on standard servlet containers or application servers and streamline the integration with security frameworks like Keycloak, which are more traditionally configured via `web.xml`.

### Issue Priority

Priority: 3

### Issue Component

Component: Hop Server

The issue names no files, tests, or entry points. Start by locating the Hop Web Server module and its current Jetty and build configuration, then determine the required servlet-container packaging and deployment behavior. Done means the web server can be exported as a WAR and deployed on a standard container with the requested Keycloak integration path.

Written by the indexing model from the issue text.