Add a workflow-organized reference under apps/docs/v5/api-reference,
covering ingest, search, content management, namespaces, organization,
and profiles, plus an overview explaining base URL, authentication, and
the Legacy-vs-Latest versioning model.
Operations, parameters, and response shapes are grounded in the in-repo
schemas and client surface (packages/validation/api.ts,
packages/validation/schemas.ts, packages/lib/api.ts) and the
conversations client in packages/tools. Register the new pages in the
docs.json navigation as a "V5 API Reference" anchor.
