Add translations & Improve code quality

Author: Jack251970

Flow.Launcher/Languages/en.xaml

@@ -590,6 +590,7 @@
     <system:String x:Key="errorTitle">Error</system:String>
     <system:String x:Key="folderOpenError">An error occurred while opening the folder. {0}</system:String>
     <system:String x:Key="browserOpenError">An error occurred while opening the URL in the browser. Please check your Default Web Browser configuration in the General section of the settings window</system:String>
+    <system:String x:Key="fileNotFoundError">File or directory not found: {0}</system:String>
 
     <!--  General Notice  -->
     <system:String x:Key="pleaseWait">Please wait...</system:String>

Flow.Launcher/PublicAPIInstance.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Specialized;
@@ -412,14 +412,12 @@ public void OpenDirectory(string directoryPath, string fileNameOrFilePath = null
 
         private void OpenUri(Uri uri, bool? inPrivate = null, bool forceBrowser = false)
         {
-            if (uri.IsFile)
+            if (uri.IsFile && !File.Exists(uri.LocalPath) && !Directory.Exists(uri.LocalPath))
             {
-                if (!File.Exists(uri.LocalPath) && !Directory.Exists(uri.LocalPath))
-                {
-                    ShowMsgError(GetTranslation("errorTitle"), $"File or directory not found: {uri.LocalPath}");
-                    return;
-                }
+                ShowMsgError(GetTranslation("errorTitle"), string.Format(GetTranslation("fileNotFoundError"), uri.LocalPath));
+                return;
             }
+
             if (forceBrowser || uri.Scheme == Uri.UriSchemeHttp || uri.Scheme == Uri.UriSchemeHttps)
             {
                 var browserInfo = _settings.CustomBrowser;