fix: use preprocessor in l1 contracts for native token checks

[SantiagoPittella]

🌟 Feature Request

📝 Description

In the L1 contracts, we are currently sending msg.value AND the _amount field with the same values to catch both native token and native eth cases.

Use the preprocessor to add checks:
In the case of native ERC20: msg.value should be zero.
In the case of native ETH: _amount should be zero.

📋 Additional Context

Most of this changes should be done in Mailbox.sol and the bridges.