Extract shared rank-formatting helper

osu.Game/Utils/FormatUtils.cs

@@ -1,6 +1,8 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using Humanizer;
+
 namespace osu.Game.Utils
 {
     public static class FormatUtils
@@ -18,5 +20,11 @@ namespace osu.Game.Utils
         /// <param name="accuracy">The accuracy to be formatted</param>
         /// <returns>formatted accuracy in percentage</returns>
         public static string FormatAccuracy(this decimal accuracy) => $"{accuracy:0.00}%";
+
+        /// <summary>
+        /// Formats the supplied rank/leaderboard position in a consistent, simplified way.
+        /// </summary>
+        /// <param name="rank">The rank/position to be formatted.</param>
+        public static string FormatRank(this int rank) => rank.ToMetric(decimals: rank < 100_000 ? 1 : 0);
     }
 }