Review pipeline initializations

[luizgrp]

          The answer seems to be in [DAC](https://developer.android.com/topic/architecture/ui-layer/state-production#initializing-state-production):

Flow APIs allow for this with the started argument in the stateIn method.

Which seems to be what NiA is using.

Then it continues:

In the cases where this is inapplicable, define an idempotent initialize() function to explicitly start the state production pipeline as shown in the following snippet:

So we should re-evaluate our cases and see when the stateIn + started WhileSubscribed is applicable.

Originally posted by @luizgrp in #2078 (comment)