Hexbear will be federating soon, there should be pinned post explaining it

Hexbear is far more likely to have users entering and using our comms, being another large socialist instance, albeit dedicated to left unity rather than Marxism like ourselves. I think there is enough of a culture change that we need to have a pinned post for hexbear users coming here explaining what kind of content/attitudes they might see here/what different rules to follow

There should also be a section dedicated to explaining to lemmygrad users to respect hexbear comm rules and what to expect from their users etc.

I think this would help ease any potential cross site struggle sessions