Investigate de-duplicating TokenType and TokenStandard

[jmrossy]

Problem

The SDK has two important enums for representing the 'kind' of a token:
TokenType
TokenStandard

TokenType came first and is tightly coupled to the different EVM token contracts.

TokenStandard came later to meet the needs of WarpCore and the Warp UI. It must support:

1. All protocols, not just EVM
2. Additional standards, not just Hyperlane ones (e.g. IBC)

Two different token types may possibly have the same token standard. Two different token standards must have different token types. This decoupling makes de-duping them tricky. It may be the case that we need to keep both degrees of freedom here.