topshift-trend: a cooldown so a chat is not notified twice about the same repo

topshift-trend, the Telegram bot that watches GitHub’s monthly trending list, learned to suppress repositories it recently notified: a repo that drops out of the top-N and comes back used to announce itself to every subscriber again. The bot now keeps a notification_history.json alongside its state and subscribers, and the scheduled check filters out keys seen inside a configurable window — NOTIFICATION_COOLDOWN_DAYS, default 30 days, 0 disables the suppression. The commit touches the config, store and main loop plus three test files, and the check’s log line now reports how many entries were suppressed next to how many notifications actually went out.