A tap right after lock lock can report success on a locked device #327

Straight after lock lock, a tap can answer tapped, exit 0, and reach nothing.

Seen on main fe42c5b and af200b6. Android 15 emulator. MobiumApp v1.0.0, home screen. An iPhone 17 Pro simulator (iOS 26.5) never reported a false success in 6 tries.

Repro

$ mobium lock lock
locked (was unlocked)
$ mobium current
dev.mobium.mobiumapp
$ mobium tap "label=Login Demo"
tapped label=Login Demo at (540, 814)
$ mobium lock unlock
unlocked (was locked)
$ mobium find testid=username
No element matches testid=username

Tap outcomes over 8 trials, on each build:

testid=username was absent after unlock in 8/8, so the two reported taps did not open the Login Demo.

Two defects:

1. A false success. A test or agent carries on as if the tap landed.
2. Exit 1 names a changing screen, and never the lock. lockedRead gives the right answer in the other trials.

iOS, 6 of 6, on fe42c5b: no element matches label=Login Demo on the current screen — the screen may have changed, run app_map again, exit 4. It is not a false success, though it doesn't mention the lock either, and current still named the app in 5 of the 6.

Possible fix

lock lock answers before the keyguard is up, so the next read still sees the app. Either wait in lockOn until the tree no longer shows the app, or check ScreenLocked before a touch on Android, and in the read-failure path that produced exit 1. I have not built or tested either.