Add ASCII file name conversion (#17580)

(cherry picked from commit 4590739)
(cherry picked from commit 3d1505d)

Author: kjac

src/Umbraco.Core/Configuration/Models/RequestHandlerSettings.cs

@@ -15,6 +15,7 @@ public class RequestHandlerSettings
 {
     internal const bool StaticAddTrailingSlash = true;
     internal const string StaticConvertUrlsToAscii = "try";
+    internal const string StaticConvertFileNamesToAscii = "false";
     internal const bool StaticEnableDefaultCharReplacements = true;
 
     internal static readonly CharItem[] DefaultCharCollection =
@@ -73,6 +74,22 @@ public class RequestHandlerSettings
     /// </summary>
     public bool ShouldTryConvertUrlsToAscii => ConvertUrlsToAscii.InvariantEquals("try");
 
+    /// <summary>
+    ///     Gets or sets a value indicating whether to convert file names to ASCII (valid values: "true", "try" or "false").
+    /// </summary>
+    [DefaultValue(StaticConvertFileNamesToAscii)]
+    public string ConvertFileNamesToAscii { get; set; } = StaticConvertFileNamesToAscii;
+
+    /// <summary>
+    ///     Gets a value indicating whether URLs should be converted to ASCII.
+    /// </summary>
+    public bool ShouldConvertFileNamesToAscii => ConvertFileNamesToAscii.InvariantEquals("true");
+
+    /// <summary>
+    ///     Gets a value indicating whether URLs should be tried to be converted to ASCII.
+    /// </summary>
+    public bool ShouldTryConvertFileNamesToAscii => ConvertFileNamesToAscii.InvariantEquals("try");
+
     /// <summary>
     ///     Disable all default character replacements
     /// </summary>

src/Umbraco.Core/Strings/DefaultShortStringHelperConfig.cs

@@ -74,12 +74,21 @@ public DefaultShortStringHelperConfig WithDefault(RequestHandlerSettings request
         {
             urlSegmentConvertTo = CleanStringType.Ascii;
         }
-
-        if (requestHandlerSettings.ShouldTryConvertUrlsToAscii)
+        else if (requestHandlerSettings.ShouldTryConvertUrlsToAscii)
         {
             urlSegmentConvertTo = CleanStringType.TryAscii;
         }
 
+        CleanStringType fileNameSegmentConvertTo = CleanStringType.Utf8;
+        if (requestHandlerSettings.ShouldConvertFileNamesToAscii)
+        {
+            fileNameSegmentConvertTo = CleanStringType.Ascii;
+        }
+        else if (requestHandlerSettings.ShouldTryConvertFileNamesToAscii)
+        {
+            fileNameSegmentConvertTo = CleanStringType.TryAscii;
+        }
+
         return WithConfig(CleanStringType.UrlSegment, new Config
         {
             PreFilter = ApplyUrlReplaceCharacters,
@@ -92,7 +101,7 @@ public DefaultShortStringHelperConfig WithDefault(RequestHandlerSettings request
         {
             PreFilter = ApplyUrlReplaceCharacters,
             IsTerm = (c, leading) => char.IsLetterOrDigit(c) || c == '_', // letter, digit or underscore
-            StringType = CleanStringType.Utf8 | CleanStringType.LowerCase,
+            StringType = fileNameSegmentConvertTo | CleanStringType.LowerCase,
             BreakTermsOnUpper = false,
             Separator = '-',
         }).WithConfig(CleanStringType.Alias, new Config