I'm introducing a `pinned_messages` table to store the information for pinning messages. `messageID` --> the corresponding pinned message. `thread` --> the thread the message belongs to. `pin_time`
--> initialized when the message is pinned to the current time. I'm adding an index on `thread` since at some point I'm going to have to query on it. The reason I'm introducing a new table, as opposed to just
adding a column to the `threads` table and storing a list of message ids, is to adhere to [[ https://www.wikiwand.com/en/Database_normalization#Satisfying_1NF | 1NF ]].
I also read up on UTF encoding on [[ https://mariadb.com/kb/en/unicode/ || MariaDB ]] and it seems fine for what I'm storing in the table.
Lastly, I'm aware I need a migration as well for this table, and it'll be added in the next diff where I introduce a new threadPermission since that'll require a migration as well. That way, I can
combine the `pinned_messages` related migrations into one.