QbzBridge QML singleton (12 properties, 8 invokables) driven by tokio
tasks via CxxQtThread. Port of auth.rs (browser OAuth loopback listener
with qbzd-style nonce, 180s timeout, cancel via JoinHandle abort,
scoped offline-gate lift for cold bundle init, D1 token-keep on network
failure / clear on explicit rejection, D4 subscription grace marks).
OfflineModeEngine + ConnectivityActor started at boot with live watch
forwarding (connectivity/captive portal/recovery banner/has-previous-
session). Boot: splash -> silent token restore -> shell | login.
Start-offline enters the guest profile. LoginScreen.qml is a faithful
port with exact msgids routed through qbz-i18n. 5 unit tests green.
km
