LEVM: Refactor the main method flow

[ilitteri]

• The new transact method should: prepare the VM for execution -> execute -> resolve the execution result -> perform the post-execution logic -> return the transaction execution report.
• execute should return an ExecutionResult.
• There should be a resolve_execution_result function that takes the ExecutionResult and returns the TransactionExecutionReport.
• The TransactionExecutionReport should be altered by the post-execution logic as needed.

[lima-limon-inc]

On it! See: #1807

[lima-limon-inc]

The new transact method should: prepare the VM for execution -> execute -> resolve the execution result -> perform the post-execution logic -> return the transaction execution report.

I think this is basically the case now. There is an if statement I'd like to remove (see here), although it has proven to be harder than expected. I'll tackle it later on.