Make staff `!tea` post to Twitter/Mastodon

[strugee]

I think it would be nice if, when conference staff !tea'd someone, Patch would syndicate that toast to social media. This would be a nice way to publicly shout out volunteers and would also have a nice side effect of generating more social media content for folks to engage with.

This should be opt-in because some of our community members may not want to be mentioned on social media. Here's the flow I'm imagining:

1. A staff member uses !tea mentioning someone
2. Patch posts the currently-existing response
3. (New behavior from now on) Patch DMs the recipient and asks if they're ok with it going to socials too, and how to refer to them on socials (could be an @ username or just a plaintext name)
4. User replies
5. Socials get posted

We'd want to restrict this to staff members for security reasons. Non-staff !teas should use the existing behavior.

[strugee]

@AlfredoMS opinions on this?