Add BeatmapInfo.LastUpdate to track the time of local changes

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -102,6 +102,14 @@ namespace osu.Game.Beatmaps
 
         public string OnlineMD5Hash { get; set; } = string.Empty;
 
+        /// <summary>
+        /// The last time of a local modification (via the editor).
+        /// </summary>
+        public DateTimeOffset? LastUpdated { get; set; }
+
+        /// <summary>
+        /// The last time online metadata was applied to this beatmap.
+        /// </summary>
         public DateTimeOffset? LastOnlineUpdate { get; set; }
 
         /// <summary>

osu.Game/Beatmaps/BeatmapManager.cs

@@ -314,6 +314,7 @@ namespace osu.Game.Beatmaps
                 beatmapInfo.MD5Hash = stream.ComputeMD5Hash();
                 beatmapInfo.Hash = stream.ComputeSHA2Hash();
                 beatmapInfo.Status = BeatmapOnlineStatus.LocallyModified;
+                beatmapInfo.LastUpdated = DateTimeOffset.Now;
 
                 if (setInfo.Beatmaps.All(b => b.Status == BeatmapOnlineStatus.LocallyModified))
                     setInfo.Status = BeatmapOnlineStatus.LocallyModified;

osu.Game/Database/RealmAccess.cs

@@ -67,8 +67,9 @@ namespace osu.Game.Database
         /// 20   2022-07-21    Added LastAppliedDifficultyVersion to RulesetInfo, changed default value of BeatmapInfo.StarRating to -1.
         /// 21   2022-07-27    Migrate collections to realm (BeatmapCollection).
         /// 22   2022-07-31    Added ModPreset.
+        /// 23   2022-08-01    Added LastUpdated to BeatmapInfo.
         /// </summary>
-        private const int schema_version = 22;
+        private const int schema_version = 23;
 
         /// <summary>
         /// Lock object which is held during <see cref="BlockAllOperations"/> sections, blocking realm retrieval during blocking periods.