Refactor EIP-7002 implementation to use contract

[jflo]

When EIP-7002 was designed, client teams had the option of calling an enshrined contract, or implementing it directly against state. When this was implemented, we chose the option of a direct implementation against the state. Since then, we've realized offering teams that choice opens up the potential for bugs, and when EIP-7251 is implemented it should be via the enshrined contract.

For consistency purposes, we should go back over the EIP-7002 implementation and alter it to be more consistent with future "requests" that are implemented via enshrined contracts.

Acceptance Criteria

• EIP-7002 depends on enshrined contract.

[Gabriel-Trintinalia]

#7263 Implement System Calls