EVM/Kernel: Unwrap basic types and use primitive types

Context

Fixes #5436 (closed). Built on top of !8460 (merged).

This MR completely removes basic.rs and instead homogeneously use U256/H256 primitive types accross all files.

Manually testing the MR

> make -f kernels.mk evm_kernel.wasm

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