[FEAT]: colocate data layer with features

[digitalbuddha]

Description

right now data is a layer that can get large, let's collapse into features

Additional Information

No response

[thebino]

I like the idea of splitting everything by feature, the current draft is a mixture: https://github.com/AndroidDev-social/DodoForMastodon/blob/main/CONTRIBUTING.md#%EF%B8%8F-structure

The reason is/was that nearly everything data related will end up in the Mastodon API. So it might be easier to keep it close to the lower layers.
But every proposal is very welcome <3