More test coverage: lockdown, purge, slowmode.
Three moderation utility commands — /lockdown, /unlock, /purge, and /slowmode — had zero test coverage at their command-dispatch layer despite being live in production for a while. All four now have real tests: permission refusal, single-channel vs. whole-server lockdown scope, a channel the bot can't manage surfacing as a skipped entry instead of silently vanishing, purge's user-filtered pagination, and slowmode targeting an explicit channel over the current one. Caught a real bug in the new test fixtures themselves along the way (a fake channel missing its .guild back-reference) before it could mask anything — no behavior changed in the bot itself.