[clone] Split runtime into devnet and mainnet

[weezy20]

This PR is a clone of #30 where we have rebased the changes on top of current main:HEAD Since this is a huge rebase and the other PR has been built without the many changes interim, it's best to keep this one separate, for nice and clean observation.

Issue #10

[evilrobot-01]

Minor thing, but do we need the word template in the runtime names? It would be easier for downstream teams if it were omitted and it's implied based on the repo name.

Then template users don't need to do anything to remove the template name when adopting, making it easier.

A counter argument is that a template perhaps provides no guarantees, so think it needs to be carefully considered.

[weezy20]

Minor thing, but do we need the word template in the runtime names? It would be easier for downstream teams if it were omitted and it's implied based on the repo name.

Template is supposed to be a placeholder. My take on this would be, given that it's a template we are free to choose whatever name we use for spec, impl strs and the runtime. Renaming things for a team would be as simple as replacing the entire string in the directory so I don't see renaming it bringing much convenience.

[stiiifff]

LGTM !