[Feature] Make BAL a dedicated type

### Describe the feature you would like currently we have https://github.com/alloy-rs/eips/blob/f733b588dbdda9d8059dbd46671e68ee593f3ef5/crates/eip7928/src/block_access_list.rs#L6-L7 we will need a pub of helpers on this type in the future, so it might be useful to add a simple new type for the vec, then we can add useful helper functions in there cc @Soubhik-10 ### Additional context _No response_