c8582fc4a2
_bot_participated_threads was an in-memory set — lost on every restart. After restart, the bot forgot which threads it was active in, requiring fresh @mentions and potentially creating duplicate threads instead of continuing existing conversations. Changes: - Persist thread IDs to ~/.hermes/discord_threads.json - Load on adapter init, save on every new thread participation - _track_thread() replaces direct .add() calls for atomic persist - Cap at 500 tracked threads to prevent unbounded growth - /thread slash command also tracks participation - 7 new tests covering persistence, restart survival, corruption recovery, cap enforcement