Previously, executeStopHooks returned immediately after the first hook
that produced valid JSON stdout, even if it was non-blocking. This
prevented subsequent hooks from executing.
This was problematic when users had multiple Stop hooks (e.g.,
check-console-log.js + task-complete-notify.sh in settings.json),
because the first hook's stdout (which echoed stdin data as JSON)
caused an early return, silently skipping all remaining hooks.
Now only explicitly blocking results (exit code 2 or decision=block)
cause an early return, matching Claude Code's behavior of executing
all Stop hooks sequentially.
Closes#1707
raki-1203