fix: start listening to backpress in lock view

It seems nothing was listening to the backpress anymore.
Fixed that by starting listening to them directly in the view
as it feels safer than listening from a distant service layer

src/app/view/Lock/useLockScreen.ts

@@ -21,6 +21,7 @@ import {
   validatePin
 } from '/app/domain/authorization/services/LockScreenService'
 import { useI18n } from '/locales/i18n'
+import { SecurityNavigationService } from '/app/domain/authorization/services/SecurityNavigationService'
 
 export const useLockScreenProps = (props: LockScreenProps): LockViewProps => {
   const [biometryEnabled, setBiometryEnabled] = useState(false)
@@ -36,6 +37,16 @@ export const useLockScreenProps = (props: LockScreenProps): LockViewProps => {
   const { fqdn } = getInstanceAndFqdnFromClient(client)
   const { t } = useI18n()
 
+  // This is intended to ensure that the backpress listener is always active,
+  // and will always quit the app when the user is on the lock screen.
+  useEffect(() => {
+    SecurityNavigationService.startListening()
+
+    return () => {
+      SecurityNavigationService.stopListening()
+    }
+  })
+
   const onUnlock = useCallback((): void => {
     if (!props.route.params?.onSuccess) return reset(routes.home)