feature: add context menu to copy message of an annotated tag (#567)

src/Resources/Locales/en_US.axaml

@@ -595,6 +595,7 @@
   <x:String x:Key="Text.Submodule.Remove" xml:space="preserve">Delete Submodule</x:String>
   <x:String x:Key="Text.Sure" xml:space="preserve">OK</x:String>
   <x:String x:Key="Text.TagCM.Copy" xml:space="preserve">Copy Tag Name</x:String>
+  <x:String x:Key="Text.TagCM.CopyMessage" xml:space="preserve">Copy Tag Message</x:String>
   <x:String x:Key="Text.TagCM.Delete" xml:space="preserve">Delete ${0}$...</x:String>
   <x:String x:Key="Text.TagCM.Push" xml:space="preserve">Push ${0}$...</x:String>
   <x:String x:Key="Text.URL" xml:space="preserve">URL:</x:String>

src/Resources/Locales/zh_CN.axaml

@@ -593,6 +593,7 @@
   <x:String x:Key="Text.Submodule.Remove" xml:space="preserve">删除子模块</x:String>
   <x:String x:Key="Text.Sure" xml:space="preserve">确    定</x:String>
   <x:String x:Key="Text.TagCM.Copy" xml:space="preserve">复制标签名</x:String>
+  <x:String x:Key="Text.TagCM.CopyMessage" xml:space="preserve">复制标签信息</x:String>
   <x:String x:Key="Text.TagCM.Delete" xml:space="preserve">删除 ${0}$...</x:String>
   <x:String x:Key="Text.TagCM.Push" xml:space="preserve">推送 ${0}$...</x:String>
   <x:String x:Key="Text.URL" xml:space="preserve">仓库地址 ：</x:String>

src/Resources/Locales/zh_TW.axaml

@@ -598,6 +598,7 @@
   <x:String x:Key="Text.Submodule.Remove" xml:space="preserve">刪除子模組</x:String>
   <x:String x:Key="Text.Sure" xml:space="preserve">確  定</x:String>
   <x:String x:Key="Text.TagCM.Copy" xml:space="preserve">複製標籤名稱</x:String>
+  <x:String x:Key="Text.TagCM.CopyMessage" xml:space="preserve">複製標籤訊息</x:String>
   <x:String x:Key="Text.TagCM.Delete" xml:space="preserve">刪除 ${0}$...</x:String>
   <x:String x:Key="Text.TagCM.Push" xml:space="preserve">推送 ${0}$...</x:String>
   <x:String x:Key="Text.URL" xml:space="preserve">存放庫網址:</x:String>

src/ViewModels/Repository.cs

@@ -1829,6 +1829,16 @@ namespace SourceGit.ViewModels
                 ev.Handled = true;
             };
 
+            var copyMessage = new MenuItem();
+            copyMessage.Header = App.Text("TagCM.CopyMessage");
+            copyMessage.Icon = App.CreateMenuIcon("Icons.Copy");
+            copyMessage.IsEnabled = !string.IsNullOrEmpty(tag.Message);
+            copyMessage.Click += (_, ev) =>
+            {
+                App.CopyText(tag.Message);
+                ev.Handled = true;
+            };
+
             var menu = new ContextMenu();
             menu.Items.Add(createBranch);
             menu.Items.Add(new MenuItem() { Header = "-" });
@@ -1838,6 +1848,7 @@ namespace SourceGit.ViewModels
             menu.Items.Add(archive);
             menu.Items.Add(new MenuItem() { Header = "-" });
             menu.Items.Add(copy);
+            menu.Items.Add(copyMessage);
             return menu;
         }