EVM:node: add support for the tx_queue in proxy mode

Checklist

• Provide automatic testing.
• Add an item in the changelog

What

meta issue: #7785

Implements logic to uses the proxy mode with the TX queue.

Why

The proxy mode is useful to folow the chain with the point of view of the rollup node. No one should uses the proxy mode to forward transaction to the chain, but as the feature it there and not yet deprecated we need to support it. This is specially true for our test suite that still has tests using the kernel in proxy mode (and so needs a proxy evm nde).

How

Instead of surcharching the tx_queue with code for a legacy/soon to be decrecated (the tx_pool in the proxy mode) I prefered to modify as much as possible the proxy.ml file. It means closure, and it's maybe less readible but I prefer that than add request to the tx_queue that we must not forgot to remove later.

Manually testing the MR

Summary by CodeRabbit

• New Features
  • Proxy nodes now support transaction queuing, enabling enhanced transaction management.
• Improvements
  • Transaction processing has been refined with optional forwarding across the system.
  • Configuration options for transaction queues have been updated for greater flexibility.
• Tests
  • Updated tests confirm the correct behavior of the new transaction queuing and forwarding features.