Copy OpenAPI

Copies the dereferenced, cycle-safe JSON fragment for just the selected endpoint.

What it does

Unlike Copy for AI (plain LLM-ready text), Copy OpenAPI returns the JSON, but already dereferenced (no $ref) and cycle-safe so it can be passed through JSON.stringify. This is done by src/document-model/cap-depth.ts, which makes a dereferenced (and possibly cyclic, for recursive DTOs) schema safe to serialize.