Holy crap auth works (#2099)

* Holy crap auth works

* Fix some usages of UserID instead of UserName

* Refactor preferences.

They be non-async now. Also faster.

* Rename DbContext.

* Guest username assignment.

* Fix saving of profiles.

* Don't store data for guests.

* Fix generating invalid random colors.

* Don't allow dumb garbage for char preferences.

* Bans.

* Lol forgot to fill out the command description.

* Connection log.

* Rename all the tables and columns to be snake_case.

* Re-do migrations.

* Fixing tests and warnings.

* Update submodule

Content.Server/Database/ServerBanDef.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Net;
+using Robust.Shared.Network;
+
+#nullable enable
+
+namespace Content.Server.Database
+{
+    public sealed class ServerBanDef
+    {
+        public NetUserId? UserId { get; }
+        public (IPAddress address, int cidrMask)? Address { get; }
+
+        public DateTimeOffset BanTime { get; }
+        public DateTimeOffset? ExpirationTime { get; }
+        public string Reason { get; }
+        public NetUserId? BanningAdmin { get; }
+
+        public ServerBanDef(NetUserId? userId, (IPAddress, int)? address, DateTimeOffset banTime, DateTimeOffset? expirationTime, string reason, NetUserId? banningAdmin)
+        {
+            if (userId == null && address == null)
+            {
+                throw new ArgumentException("Must have a banned user, banned address, or both.");
+            }
+
+            if (address is {} addr && addr.Item1.IsIPv4MappedToIPv6)
+            {
+                // Fix IPv6-mapped IPv4 addresses
+                // So that IPv4 addresses are consistent between separate-socket and dual-stack socket modes.
+                address = (addr.Item1.MapToIPv4(), addr.Item2 - 96);
+            }
+
+            UserId = userId;
+            Address = address;
+            BanTime = banTime;
+            ExpirationTime = expirationTime;
+            Reason = reason;
+            BanningAdmin = banningAdmin;
+        }
+    }
+}