Sign-in: passkey first, codes as a deliberate second choice

If your account has both a passkey and an authenticator app, signing in now offers the passkey first. Your browser's passkey prompt opens by itself; if you dismiss it you can try again, or choose Use a code instead to enter an authenticator or backup code.

• Passkey only: the code box asks for a backup code, and says why.
• Authenticator app only: nothing changes.
• Settings → Security: you can now rename a passkey, so you can tell your devices apart.

Also fixed: signing out after the page had been idle for a while could leave you signed in. Logout now ends the session reliably.