OptionalfetchImpl: FetchLikeRV5 "forget me": asks the server to archive this visitor's memory and clear the VisitorKey
linkage. The caller is responsible for clearing the durable cookie afterward
(clearVisitorKey). Public endpoint — the durable key is the proof. Never throws.
Mints a fresh guest session. Throws on a non-2xx / unsuccessful response.
OptionalvisitorKey: stringthe durable returning-visitor anchor from the first-party cookie, if present — the server uses it to chain this visit to the visitor's prior conversation (gated on the widget's RememberReturningVisitors toggle). Omit on a first visit; the server mints one when remembering is on.
Refreshes the guest session (server re-mints by the same key). Carries the visitor anchor so the refreshed session keeps the same returning-visitor identity.
OptionalvisitorKey: stringW5 magic-link upgrade ("Verify it's you"): asks the server to email a verification link scoped to
the widget's app. On success the visitor receives an email; clicking it redeems a VERIFIED session
JWT (via the existing /magic-link/redeem). The host page hands that token back to the widget,
which calls transport.UpdateToken(verifiedToken) to swap it in — the live conversationId is
preserved because the transport holds it. Never throws; returns a structured result for the UI.
RV4 (magic-link upgrade path): after the visitor verifies and the widget swaps in the VERIFIED token, promote their anonymous returning-visitor trail to the verified record. AUTHENTICATED — the verified token is sent as a Bearer credential; the server reads the verified email from it. Never throws; returns a structured result.
StaticMsMilliseconds until the given session should be refreshed (never negative).
Talks to the widget guest-session endpoints. One instance per mounted widget.