Squad Briefings 2: The Briefening (#4539)

# About the pull request

Adds optional briefing rooms in place of long-rest bunks (moved further
north and south respectively) that don't replace standard briefing.

Excuse for me having to make a new PR, I fucked up the old branch so
beyond repair I had to close it (next time I won't mess around with
merge conflicts and just trust the hook)

# Explain why it's good for the game

Gives SLs a platform where they can host anything they want. As well ,
if command wants to brief the SLs and then have the SLs brief squads
they can also do that.

The old squad briefing room PR was cool, its just it was replacing
instead of adding. Here I hope to satisfy both camps.


# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

![map](https://cdn.discordapp.com/attachments/746325498896056329/1156699977750413352/2023-09-27_22.12.02.png?ex=6515ec4d&is=65149acd&hm=c3714095cc2af47b74f98730fbde3a813258ee5cac50664f7170d5fa41cb426e&)


</details>


:cl:
mapadd: New Squad Briefings south and north of normal briefing! Feel
free to use them to your heart's content.
maptweak: Moved long-rest bunks further north and further south of where
they were originally
/:cl: