Add Note severity and changes UI of administrative notes (#39808)

* Adds note_severity and updates dbconfig. New SQL stuff too.

* whoops please don't hack into my database >:^(

* UI change, changed how it's stored in the DB, removed some queries when it returns, changed stuff to key.

* Update sql_message_system.dm

* this was not defined

* random indent

* wait how did this get here

* okay enough web edits I promise

* just kidding I got u

* Update common.css

* Added buttons, changed UI again, standardized the inputs, added severity for appearance bans, fed the dog

* forgot about the banning panel

* added an asset cache

* corrects asset datum var name

SQL/tgstation_schema_prefixed.sql

@@ -254,6 +254,7 @@ CREATE TABLE `SS13_messages` (
   `round_id` int(11) unsigned NOT NULL,
   `secret` tinyint(1) unsigned NOT NULL,
   `expire_timestamp` datetime DEFAULT NULL,
+  `severity` enum('high','medium','minor','none') DEFAULT NULL,
   `lasteditor` varchar(32) DEFAULT NULL,
   `edits` text,
   `deleted` tinyint(1) unsigned NOT NULL DEFAULT '0',