Add macOS runtime check to clipboard file operations and fix CopyFileMenuItem name placement

Author: Ruben2776

src/PicView.Avalonia/Clipboard/ClipboardFileOperations.cs

@@ -1,4 +1,4 @@
-using System.Diagnostics;
+using System.Runtime.InteropServices;
 using Avalonia.Platform.Storage;
 using PicView.Avalonia.Animations;
 using PicView.Avalonia.Navigation;
@@ -124,6 +124,12 @@ public static async Task CopyFileToClipboard(string? filePath, MainViewModel vm)
             return;
         }
 
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
+        {
+            // TODO add clipboard file copy on macOS 
+            return;
+        }
+
         var tasks = new[]
         {
             AnimationsHelper.CopyAnimation(),

src/PicView.Avalonia/Views/Main/MainView.axaml

@@ -896,8 +896,7 @@
                 CommandParameter="{CompiledBinding PicViewer.FileInfo.Value.FullName,
                                                    FallbackValue=''}"
                 Header="{CompiledBinding Translation.Copy.Value,
-                                         Mode=OneWay}"
-                x:Name="CopyFileMenuItem">
+                                         Mode=OneWay}">
                 <MenuItem.Icon>
                     <Path
                         Data="{StaticResource CopyGeometry}"
@@ -996,7 +995,8 @@
                 Header="{CompiledBinding Translation.CopyFile.Value,
                                          Mode=OneWay}"
                 IsEnabled="{CompiledBinding PicViewer.FileInfo.Value,
-                                            Converter={x:Static ObjectConverters.IsNotNull}}">
+                                            Converter={x:Static ObjectConverters.IsNotNull}}"
+                x:Name="CopyFileMenuItem">
                 <MenuItem.Icon>
                     <Path
                         Data="{StaticResource CopyGeometry}"