Can't use bot in forum topics

At present, Vortex does not join forum topics as they are created, so moderative commands cannot be used in forum topics.

Start by locating the code that handles Discord forum-topic creation and the bot's joining behavior. Trace how moderative commands are made available in regular forum topics, then apply the same expected behavior to newly created topics. Done means Vortex joins new forum topics so its moderation commands can be used there; verify with a Discord test or existing project checks.

Written by the indexing model from the issue text.