fix: check issue state not labels in merged-PR catch-up

Closed issues can still have labels; the old `if not labels` guard
never fired for issue #272, so the loop retried the no-op close every
minute and never reached the ToPlan/Ready issue logic.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/agent_loop.py

@@ -912,9 +912,11 @@ def _run_loop() -> int:
         if not m:
             continue
         issue_num = int(m.group(1))
-        labels = _get_issue_labels(issue_num)
-        if not labels:
-            # Issue is likely already closed — skip.
+        try:
+            issue_data = _tea_get(f"/repos/{REPO}/issues/{issue_num}")
+        except RuntimeError:
+            continue
+        if issue_data.get("state") != "open":
             continue
         pr_number = pr["number"]
         print(f"Catch-up (merged PR): PR #{pr_number} for issue #{issue_num} was merged — closing.")