List scope catalog + presets

Return all API v2 scopes and named preset bundles.

No database access is performed — the catalog is derived from in-memory constants. Requires clients:read scope because anyone who can view API clients needs access to the scope catalog.

Returns a JSON:API response with:

• data: list of scope resource objects (type, id, attributes)
• meta.presets: named scope preset bundles

Required OAuth scope: clients:read