For long running resource consuming tasks you could use the Conversion Server. There is a community project that shows how to run a task in the background.
If your task is does not need a lot of server resources, you could use async/await or promise call from a Javascript Method. E.g. a button click starts the JS Method. It can then call the various server Methods asynchronously . I used this approach in one of my previous customization and it worked pretty well. You can also react on errors and result.
I never used CommitTransaction() so far, so I cannot tell you if this would be a preferable approach.
