Add BridgedGovernor

[CodeSandwich]

The communication happens over LayerZero v2. It's completely one-way, the DAO on one chain directly interacts with LayerZero contracts, and the governor on the other chain executes whatever it gets from the bridge.

This PR includes the governor and a few scripts that are the base for communication. As of now the scripts do the communication from an EOA sending transactions on Sepolia to a governor deployed on Polygon Mumbai. It will be modified to construct the real world communication when we choose the chain where we want to deploy. The configuration will be different and the transactions sent on Sepolia will be wrapped in messages executable by the DAO.