Accepts any of the three token kinds and echoes back the identity behind
it: {kind:"guest", guestId, kcId, gemeindeId} for a Konfi token, or
{kind:"user", userId, email, memberships, isLeitungsteam} for an Authentik
or local Teamer token. Lets the client pick the right screens without
decoding the JWT itself.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>