openBundle property
Opens an installed bundle. The tier supplies this — the core knows what is installed, only the shell knows how to put it on screen.
Without it a harness has to reach the bundle through the launcher, which means registering it in the tier's app list first; a probe that edits the user's app registry to run is a probe that changes what it measures (and loses whatever the running copy writes back).
Implementation
final Future<bool> Function(String bundleId)? openBundle;