EVM mockup: L2 eth-kernel block prototype

Context

Fixes #4953 (closed).

In a follow-up issue #4952 (closed) we will produce blocks from blueprints introduced in !7764 (merged). We will be able to do test in that MR using the octez-smart-rollup-wasm-debugger.

The introduced paths you will encounter while reviewing are based on Thomas P.'s work on the EVM design.

Manually testing the MR

Will be done in an upcoming MR resolving #4952 (closed).

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR