re: don't let zombie emulators fool the liveness check

Container PID 1 is `sleep infinity` and never reaps, so every emulator this
script kills stays as a <defunct> entry that `pgrep -x` still matches -- after
a few captures the script always believed one was running. Same trap as the
Xvfb check. Ask ps for the process state and skip anything in Z.

tools/re-capture/grab_tutorial.sh

@@ -31,8 +31,12 @@ ensure_display(){
 step(){ vgamepad dpad "$1"; sleep 0.2; vgamepad dpad center; sleep 0.6; }
 shot(){ screenshot "$SD/$1" >/dev/null 2>&1; }
 
+# Container PID 1 is `sleep infinity`, which never reaps, so every killed
+# emulator stays as a <defunct> entry that `pgrep` still matches. Ask ps for the
+# state and ignore anything zombie, or this always thinks one is running.
+alive(){ ps -o pid=,stat= -C xenia_canary 2>/dev/null | awk '$2 !~ /^Z/ {print $1}'; }
 pkill -x xenia_canary 2>/dev/null; sleep 2
-pgrep -x xenia_canary >/dev/null && { pkill -9 -x xenia_canary; sleep 2; }
+[ -n "$(alive)" ] && { kill -9 $(alive) 2>/dev/null; sleep 2; }
 rm -f /dev/shm/xenia_memory_* /dev/shm/xenia_code_cache_* 2>/dev/null
 
 ensure_display