Link one received inventory item to an existing watch, or remove its link.

Private and no-store. No catalog quota, paid read, public cache or CORS grant. Requires the human account cookie and CSRF. Installation tokens and wide API keys cannot select watches. The item must be present in this active installation. The watch must already be active and owned by the account. Set alvo to null to remove a link, including after item removal. An exact retry writes nothing. Changed links share the global 512 registrations per day. This creates no watch, charge or approval. Returns: { vinculado }