pentaho/pentaho-kettle ? reverse-engineered prompt

I want you to build me a working Pentaho Data Integration style app, the kind of desktop tool people use to design and run ETL jobs and transformations. It should have the core engine, a usable UI, database connection dialogs, and support for plugins so the main workflows feel complete.

Please make it build cleanly with Maven and Java 11, and keep it in a state where I can package it and run the tests. If anything depends on current docs or setup details, look them up online and follow the project’s own conventions. I care most that it launches, the main features are wired together, and the codebase feels like a real production project rather than a mockup.