Support new ways to handle assets (JSBundling, Propshaft)

[hschne]

Is your proposal related to a problem?

Rails 7 introduced several new ways to deal with assets. There are various JS and CSS Bundlers, Importmaps, and also Propshaft which will replace Sprockets sooner or later.

Rails Mini Profiler currently only supports Webpacker and Sprockets. It still works even if the user uses Importmaps (as long as they also use Sprockets).

Describe the solution you'd like

Investigate if RMP works if the user uses Propshaft. Investigate how it works if the user decides to not use Webpacker but some other JS Bundler (see JS Bundling)

Fix any issues that arise so that RMP can be used by new projects using different setups.