Hosting Client ID Document on Solid Storage

Ac currently defined Client ID Document MUST use normative JSON-LD @context, so it has to be compacted with it. Solid Storage doesn't guarantee that compaction is being preserved for RDF-Sources.

We need to double-check if Solid Storage could guarantee that. At the same time, we should gather feedback from existing implementation on how important that feature is for them. Most (all?) plain OIDC implementation doesn't support client registrations published externally as a resource on the web. Fetching them needs to be implemented as a custom future, possibly this extra functionality could take care of parsing RDF and compacting it with provided JSON-LD @context. Personally, I find it more practical to let consumers take care of compacting with a @context they rely on.

The issue names Solid Storage, RDF-Sources, JSON-LD @context, and externally published client registration resources, but no repository files or tests. Start by checking whether Solid Storage preserves JSON-LD compaction and gathering feedback from existing implementations; done means deciding and documenting whether storage or consumers handle compaction.