Support status=proven for soft confirmations

[kpp]

https://github.com/chainwayxyz/secret-sovereign-sdk/blob/14116dd1a31aa6880bc2b79a308b16cf6784f4ef/full-node/db/sov-db/src/ledger_db/rpc.rs#L305

So far we have status = "trusted" or "finalized".

[eyusufatik]

TODOs:

• [x] Create enum for status - trusted, finalized, proven. Please documentate each carefully.
• [x] Use this in softconfirmationstatus