While editing the file in Excel was on option I ultimately plan to delegate the task and so wanted something simple, clean and easy to use.
As there is no state, and no cookies, hosting on GitHub pages felt like an easy solution. The solution is vibe coded with Kiro and the source code is available at https://github.com/cactus-bm/csvprocessor/ and pull requests are welcome.
The project is hosted on my company's Github and licensed under MIT