fix(l2): fixes and cleanup of to_execution_db()

[xqft]

Motivation

Prover's execution was failing because of wrong data in the ExecutionDB. There were also some cases where data was missing but the current tests didn't catch it.

Description

• fixes saving final storage values instead of initial ones.
• fixes saving only touched storage values, instead of read ones too.
• removes unused new_store
• simplifies code

[github-actions]

Lines of code report

Total lines added: 0
Total lines removed: 49
Total lines changed: 49

Detailed view

+---------------------------------------+-------+------+
| File                                  | Lines | Diff |
+---------------------------------------+-------+------+
| ethrex/crates/vm/backends/levm/db.rs  | 214   | -1   |
+---------------------------------------+-------+------+
| ethrex/crates/vm/backends/levm/mod.rs | 642   | -48  |
+---------------------------------------+-------+------+

[xqft]

I'm not sure yet if "written" values (the ones included in execution_updates) are included in the "accessed" values set, if so then the function could be simplified a lot, but that depends in the LEVM implementation (if it always calls a getter for an updated value), so for now the function chains both sets and gets every value.

[tomip01]

Nice!