Optionalmandate0.57.0 — the presentable half of the user-signed approval, present only
when the approval passed a passkey step-up on the first-party surface:
intentDigest is a sha256 of the confirm's canonical intent (tool,
arguments, scope, id, time), credentialId the passkey that signed a
challenge bound to it, signedAt when. The signature itself stays on
the server; this is the receipt a host can show and log.
OptionaloutcomeOptionaloutcomeAbsent from older servers — read absent as unrecognized.
Optionalretryable
confirmAction's response.outcomeis prose for a person;outcomeClassis the field to switch on.