fix(settings): Fix back button and side panel when opening settings

[Twixes]

Problem

1. Quoting @rafaeelaudibert:

   redirecting from project- to environment- [is] not replacing the URL, it's simply adding a new entry, so you need to click the back arrow twice

2. Quoting @annikaschmid:

   The project settings button is not working anymore ["Configure" in session replay]

Both apply only behind the environments feature flag.

Changes

1. The cause of redundant history items was an awkward interaction between urlToAction and actionToUrl in settingsSceneLogic:
   urlToAction called selectLevel/selectSection with the redirected path, which caused those actions' actionToUrl handlers to create new history items.
   Now selectLevel/selectSection replace the current history item, and we no longer use them in the settings scene.
   The settings scene uses URLs instead, which is overall better ergonomics (e.g. you can now use "Open in new tab" in settings).

2. The redirect only applied in settingsSceneLogic, but we also now have analogous logic for side panel settings in the lower-level settingsLogic.

How did you test this code?

Clicked around in this case.

[github-actions]

Size Change: 0 B

Total Size: 1.11 MB

ℹ️ View Unchanged

Filename	Size
frontend/dist/toolbar.js	1.11 MB

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[rafaeelaudibert]

I definitely need to study Kea better :). Even if I had found the right file I don't think I'd have been able to solve it.

Thanks for the fix! Tested locally and it looks good :)