=== Probe 3a: stop_hook_active=true with failing cmd → expect exit 0 ===
[probe3a] exit=0

=== Probe 3b: stop_hook_active=false, verification passes → expect exit 0 ===
[probe3b] exit=0

=== Probe 3c: stop_hook_active=false, verification fails → expect exit 2 ===
[probe3c] exit=2

=== Probe 3d: stop_hook_active=true, verification fails → must still be exit 0 ===
[probe3d] exit=0
