Persist Harbor agent stop timing

Author: rgarcia

src/clawbench/runtime/harbor/wrap-harbor-agent.sh

@@ -31,6 +31,7 @@ agent_pid=$!
   while kill -0 "$agent_pid" 2>/dev/null; do
     if [[ -f "$stop_file" ]]; then
       detected_at=$(date +%s.%N)
+      printf '{"stop_detected_at":%s,"signal":"INT"}\n' "$detected_at" >"$stop_result"
       kill -INT "$agent_pid" 2>/dev/null || true
       for _ in $(seq 1 20); do
         kill -0 "$agent_pid" 2>/dev/null || break
@@ -39,7 +40,6 @@ agent_pid=$!
       if kill -0 "$agent_pid" 2>/dev/null; then
         kill -TERM "$agent_pid" 2>/dev/null || true
       fi
-      printf '{"stop_detected_at":%s,"signal":"INT"}\n' "$detected_at" >"$stop_result"
       exit 0
     fi
     sleep 0.1