[Contract] Proper Handling of Prover Bonds

[linoscope]

Problem:

In the latest version of the Taiko inbox, the assigned prover is hard-coded to be the msg.sender of TaikoL1.sol (related PR). This is problematic since, with a preconf protocol, the msg.sender will be the preconf AVS contract instead of the proposer itself. As a result, the prover bond is accounted for from our AVS contract, TaikoTaskManager.sol, instead of the proposer.

Potential Solution(s):

• Do accounting for per-proposer bonds and manage approvals and withdrawals of taiko tokens through the task manager.
• Modify the Taiko inbox contract to (re)decouple the proposer from the prover.