feat: Allow Swap Commits in Revision Compare

src/Models/Commit.cs

@@ -6,7 +6,7 @@ using Avalonia.Media;
 
 namespace SourceGit.Models
 {
-    public class Commit
+    public class Commit: IObjectId
     {
         public static double OpacityForNotMerged
         {

src/Models/IObjectId.cs

@@ -0,0 +1,7 @@
+namespace SourceGit.Models
+{
+    public interface IObjectId
+    {
+        string SHA { get; }
+    }
+}

src/Models/Object.cs

@@ -9,7 +9,7 @@
         Commit,
     }
 
-    public class Object
+    public class Object: IObjectId
     {
         public string SHA { get; set; }
         public ObjectType Type { get; set; }