Refactor initiazable, Community navhost navigation and fix rare crash in inbox

[MV-GH]

• Removes initiaziable and replaced it with viewmodel constructor, this is more safe
• Remove Community root and complex viewmodel sharing. This simpliflies the logic and prevents the need for a "redirect" hack to make deeplinks work for communities
• Add logic to make forward passing of Parcelable possible (sendReturn, getPrevReturn)
• Replace rootChannel and takeDepsFromRoot
• Fixes for rare crash in inbox

Fixes #1208
Fixes #1211

@nahwneeth If interested

Just realized that the "forward passing" that I made, is just a reinvention of the rootChannel and takeDepsFromRoot

Hmm not sure which one is better atm

Edit:
I have chosen for my "reinvention" naming is still open for debate. The reason I took this over existing rootChannel is:

• sender is now not a composable which gives it more freedom,
• it is cleaner, the function itself, and the useability,
• It should survive process death now
• Should be leaner, as it does not use a ViewModel as intermediate storage

I tested everything change by change

[dessalines]

I have a few concerns about moving the initialized data completely out of the viewmodels, but I mostly blame the jetpack-compose tutorials for not having good examples for how to how to handle intialized data in conjunction with routing.

At some point we might have to entertain moving nearly all the variables out of the viewmodels (and possibly into a stored app state), and have them only consist of functions. When I initially wrote jerboa, the tutorials I'd followed recommended either one, but then most of their examples had data live in the viewmodels.

I trust you and nahweenth's additions for the correct way to do this. Once you get the conflicts resolved, feel free to merge anytime.

[dessalines]

This seems like the heart of it here, just an alternate way to send initial data, and remove it from the model.

[MV-GH]

Even before Jetpack compose passing data between activities was never really done cleanly.

Take a look at IfR does, it uses intents to pass data between activities and Preferences API for persistence

https://github.com/Docile-Alligator/Infinity-For-Reddit/blob/02278263579d76f88eef9c643bd7ace412f99985/app/src/main/java/ml/docilealligator/infinityforreddit/activities/SearchActivity.java#L65-L75

Yeah basically. The big difference here, compared to consumeReturn, is that it never removes the data from the route, it only gets removed when the screen gets popped from backstack.