Reported: EDIT on + ON-AIR on, signed out → the button reads "Test Stream" and cannot be pressed.
Cause: the primary button bound straight to StartTestCommand, whose CanExecute needs a connection.
StartSession already routed signed-out ON-AIR to the sign-in flow; the test path bypassed it.
The route is now explicit and pure: RouteFor(kind, connected) → SignIn | Record | Live | Test. The
primary command calls SignInAsync for the SignIn route, BeginTestStream for Test, StartSession
otherwise — so the label, the action and the sign-in fallback cannot drift apart. Pinned in
SessionStartDecisionTests for both live and test, connected and not.