(v0.6): Controller Registration

[prdlk]

Is this associated with a milestone?

• I have confirmed this is an OKR tracking issue

Objective

The goal is to have on-chain abstracted accounts that leverage DWNs and are powered by DID controllers.

Task List

• Implement accountstd interface for Sonr Accounts #1114
• Create MsgExecute with UCAN Token for Verification #1115
• #1116
• (x/did) Destroy unclaimed and expired Controllers on EndBlock #1117