make #market-offers a forum channel

this is a discord server suggestion but in the current state of market-offers you often see the same few messages day by day from people reposting their message so that they can be seen by a potential buyer/seller.

This can bloat the chat especially if the message is a large one that gets reposted by the user a ton, so I suggest making the #market-offers channel a forum channel instead.

This change would make it easier to see whats being sold/bought, but also will make it easier to buy/sell items with the built-in search bar for forum channels.

plus large market messages would no longer overshadow smaller requests for stuff