Investigate and refactor mock rollup for committing states

[Farhad-Shabani]

Description

While writing token transfer tests #36, we encountered a roadblock due to the lack of access to proof of commitments on our mock rollup. Therefore, we were unable to craft any IBC messages that require a commitment proof, resulting in the incomplete execution of the token transfer test from the mock rollup to the mock cosmos chain. In this case, MsgRecvPacket couldn't be constructed.

Proposal

This necessitates a deeper investigation into how committing states work in the Sovereign SDK. Subsequently, we should consider refactoring our mock rollup abstraction to allow the persistence of pending changes in a WorkingSet and the ability to roll forward the execution.