Split message/proxy data up in MessageContext and ProxyMember

PluralKit.Core/Database/Functions/DatabaseFunctionsExt.cs

@@ -0,0 +1,25 @@
+using System.Collections.Generic;
+using System.Data;
+using System.Threading.Tasks;
+
+using Dapper;
+
+namespace PluralKit.Core
+{
+    public static class DatabaseFunctionsExt
+    {
+        public static Task<MessageContext> QueryMessageContext(this IDbConnection conn, ulong account, ulong guild, ulong channel)
+        {
+            return conn.QueryFirstAsync<MessageContext>("message_context", 
+                new { account_id = account, guild_id = guild, channel_id = channel }, 
+                commandType: CommandType.StoredProcedure);
+        }  
+        
+        public static Task<IEnumerable<ProxyMember>> QueryProxyMembers(this IDbConnection conn, ulong account, ulong guild)
+        {
+            return conn.QueryAsync<ProxyMember>("proxy_members", 
+                new { account_id = account, guild_id = guild }, 
+                commandType: CommandType.StoredProcedure);
+        }  
+    }
+}