own-host page job can flake with exit 245: the LV2 probe never closes its JACK client #110

tests/own_host_lv2_probe.py (lines 60-80) returns from main() without jack_deactivate / jack_client_close. A SIGSEGV in interpreter teardown while libjack's thread still fires the ctypes callback gives returncode -11, which the page reports as 245 (job 118262529096, run 39311664834 attempt 1, right after the gain check passed). Close the client, or os._exit after the verdict.

Found in the review of #108.