Organize dwds APIs better around IDs/remoteObjects/Instances

We have different APIs that take a Dart String ID, a Chrome String ID, a Chrome RemoteObject, or an InstanceRef. Sometimes we want to be able to accept less information (e.g. Dart API calls normally just give us a Dart objectId.) But sometimes we have more information internally and we end up throwing it away or duplicating functionality with different arguments. It would be nice if we could rationalize these to be able to use the information if available. Maybe it makes sense to have something like DartUri for object references. But that might also just be over-complicated. Or maybe we could do something interesting with extension methods.

No files, tests, or entry points are named. Begin by inventorying the DWDS APIs that accept Dart IDs, Chrome IDs, RemoteObjects, or InstanceRefs; done would require an agreed, consistent reference design that preserves available information without duplicated APIs.

Written by the indexing model from the issue text.