...ons = data if isinstance(data, list) else data.get("conversations") or data.get("data") or []
if not isinstance(conversations, list):
    raise SystemExit("Unbekanntes JSON-Format: keine Conversation-Liste gefunden.")

count = 0
for idx, convo in enumerate(conversations, start=1):
    title = safe_name(convo.get("title") or f"conversation_{idx:04d}")
    cdate = ts_to_datestr(convo.get("create_time"))
...