Adopt alloy types for transaction types

[Wodann]

While working on #786, I investigated using alloy-rs's TxEip7702 type, but wasn't able to use those types side-by-side with our existing transaction types.

TxEip7702 would be equivalent to our transaction::request::Eip7702. To obtain a signed transaction, alloy uses Signed<TxEip7702>, which adds pre-computation of a tranaction_hash, RLP encoding/decoding, etc.

One aspect of EDR that wasn't easily transferred to types from alloy was the ability to have a "fakeable signature" which we support.

Definition of Done
Investigate and refactor transaction types to reuse alloy types and tests