fix(gh-monitor): instruct agent to post acknowledgment reply before doing any work

tools/gh-monitor/poll.py

@@ -174,10 +174,13 @@ def dispatch_agent(repo_slug: str, pr: dict, event: dict) -> None:
         f"URL: {url}\n\n"
         f"Instructions:\n"
         f"1. Read the full PR and the comment at the URL above.\n"
-        f"2. Reply to the comment on GitHub with a thoughtful response.\n"
+        f"2. IMMEDIATELY post a reply to the comment on GitHub acknowledging you have "
+        f"read it — even if you haven't done the work yet. Something like "
+        f"'Got it, looking into this now.' This must happen first, before any code changes.\n"
         f"3. If the comment requests a code change, implement it on the PR branch, "
         f"commit, and push.\n"
-        f"4. Keep replies concise and technical."
+        f"4. Post a follow-up reply with what you did (or why no change was needed).\n"
+        f"5. Keep replies concise and technical."
     )
 
     job_name = f"gh-monitor-pr{number}-{event.get('id', 'evt')}"