DidResolver and UniversalResolver

[frankhinek]

Context

Currently DID resolution has been implemented as follows across the Web5 SDKs:

Kotlin

• DidResolver type that has a single function resolve().
• DidResolvers concrete implementation of a "universal resolver" that can resolve DIDs using multiple registered DID method implementations.
• DidMethod type that has a methodName property and create(), resolve(), and load() functions. Each concrete DID method implementation (e.g., DidJwk, DidDht, etc.) implements DidMethod.

JS

• Missing a type for DidResolver.
• DidResolver is a concrete implementation of a "universal" DID Resolver & DID URL Dereferencer with both resolve() and dereference() functions.
• DidMethod base class that each concrete DID method implementation (e.g., DidJwk, DidDht, etc.) implements. DidMethodApi type that has a methodName property and create() function and DidMethodResolver type that has a methodName property and resolve() function. Note: This approach is a consequence of TypeScript not having the same flexibility as Kotlin in being able to use types with classes that has static methods.

Go

• Resolver implementation of a "universal resolver" that can resolve DIDs using multiple registered DID method implementations.
• Each concrete DID implementation (e.g., DidJwk, etc.) implements the resolve function.

Proposed Change

Web5 JS dids package will introduce a DidResolver and DidUrlDereferencer type. The DidResolver type will mirror the type in Kotlin and will only have the resolve function like is the case in Web5 Go. Currently DID URL Dereferencing is only used in the Web5 JS and will remain optional in other SDKs. The current DidResolver in JS that resolves DIDs for multiple methods will be renamed UniversalResolver.