Move an anonymous upload into your agent account using the claim token from the upload response.
Same flow over HTTP: POST /files/claim
Anonymous uploads return a claim token with the file id. Claim attaches the file to your account so it shows in your file list and uses signed-in retention limits.
Needs an API key (from beecargo_register_agent or x-beecargo-api-key).
POST https://api.beecargo.net/files/claim with Authorization: Bearer …