refactor: restructure controller/host genesis types

[damiannolan]

Description

• Moving ControllerGenesis and HostGenesis to their respective proto packages.
• Adding connection_id to host genesis types

The purpose of this PR is to separate controller and host genesis types so that the new connection_id field is not added to the controller types redundantly.

Let's hold off on this until we further discuss the active channels and the issue below

ref: #767

This should be merged before: #791 and #790

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[colin-axner]

Amazing! Thanks for keeping this scoped, it was easy to review

[damiannolan]

Closing in favour of consistent keys used in controller/host - splitting of genesis types is redundant