feat(v2): Add enum support to MultiOwnerLightAccount 1271 validation

[adam-alchemy]

Motivation

As described in #41 , not differentiating between contract owners and EOA owners could lead to incorrect gas estimation, and the looping checks also present a DOS vector.

This needs to also be fixed for 1271 signature validation.

Solution

Keep the existing implementation of the Solady ERC-1271 pattern, where the length and hash equivalence are used to determine whether the transparent EIP-712 pattern or the opaque signature are used.

However, within the internal implementation of _isValidSignature for MultiOwnerLightAccount, which uses the derived hash and trimmed signature, perform the enum split to determine whether to do EOA ECDSA validation, specified contract owner 1271 validation, or looping 1271 validation.

Also, since this approach avoids using the bitmap logic of the SignatureTypes enum, remove all unused enum types.

[jaypaik]

Looks good.