fix(ralph-loop): capture check_output status safely under set -e

When the agent emits no promise signal, check_output returns 1 (continue).
Under set -euo pipefail, a bare function call returning non-zero exits the
script before status=$? can capture it. Fix: use the || idiom so the
non-zero return is handled rather than triggering set -e.

Agent: human
Tests: N/A
Tests-Added: 0
TypeScript: N/A

ralph-loop.sh

@@ -491,8 +491,7 @@ for i in $(seq 1 "$MAX_ITERATIONS"); do
   run_agent "$i" build
   logfile="$LOG_DIR/iteration-${i}.log"
 
-  check_output "$logfile"
-  status=$?
+  status=0; check_output "$logfile" || status=$?
 
   case $status in
     0)