fix: assign_teams seed에 current_stage 포함 (디스크 JSON 완전성)

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

assign_teams.py

@@ -349,7 +349,7 @@ def main():
         data = json.loads(data_path.read_text(encoding="utf-8"))
     else:
         data = {
-            "settings": {"voting_open": True},
+            "settings": {"voting_open": True, "current_stage": "intro"},
             "titles": {},
             "tie_breaks": {},
             "votes": [],
@@ -358,12 +358,15 @@ def main():
     ensure_topics_seeded(data)  # 신규
     # 누락 키 보강
     for k, v in [
-        ("settings", {"voting_open": True}),
+        ("settings", {"voting_open": True, "current_stage": "intro"}),
         ("titles", {}),
         ("tie_breaks", {}),
         ("votes", []),
     ]:
         data.setdefault(k, v)
+    # 기존 settings에 누락된 nested 키 보강
+    data["settings"].setdefault("voting_open", True)
+    data["settings"].setdefault("current_stage", "intro")
 
     data_path.write_text(
         json.dumps(data, ensure_ascii=False, indent=2),