Use custom logic for fragment back stack

[nielsvanvelzen]

This is a custom implementation of the back stack for our destinations. Previously, we used the back stack from the fragment manager but this didn't really work for us.

The problem was that we had to work around some shortcomings in the fragment manager due to how our destinations work. Specifically the "replace" action, mostly used when going from video player -> next up -> video player.

The way we made the replace action work was to pop the last item from the back stack, and then add a new item. This would result in the fragment before the video player (often the details page) to be resumed to then be replaced with the video player immediately after, because popping cannot be done in a transaction.

By replacing the back stack with our own implementation we have more control over this behavior and we can directly replace the fragment instead. Most of this logic is implemented in a custom view.

Changes

• Refactor navigation logic to create our own backstack instead of relying on the fragment manager to allow proper destination replacement

Issues

Fixes #3950
Fixes #3926
Fixes #2800
Fixes #3931