Avoid using privileged intents

[Scrumplex]

As we are using this bot on the Prism Launcher Discord, we now have to avoid or justify the use of privileged intents for Letterbox.

Your app's current privileged intents:

• Guild Members
• Guild Presences
• Message Content

I think we can easily justify message content, but the other two we might be able to avoid.

[Scrumplex]

It seems like we aren't actually using Guild Presences? At least our serenity client is only initialized with message content and guild members

[Scrumplex]

Okay after checking the code, this seems to be only used to notify the ticket thread if a member rejoins the server. We could omit that feature if Discord doesn't approve of it. I'll write justifications for both of the intents that we actually use for now

[TheKodeToad]

I think we can easily justify message content, but the other two we might be able to avoid.

I think we can read DMs anyway - IIRC they are an exception
Just won't be able to do multi-liners (IIRC Discord removed the ability to do them with slash commands) :(
Edit: we can, of course just ping the bot as the prefix (already works)

[TheKodeToad]

Considering an opt in with DISCORD_MESSAGE_CONTENT_INTENT=1 and DISCORD_GUILD_MEMBER_INTENT=1