[Breaking change]: ASCII encoding of media file names from V16

[kjac]

Description

This PR introduces the option to ASCII encode media file names in V13.6 and V15.1, similarly to how URL segments are ASCII encoded by default.

To maintain backwards functional compatiblity, the option is introduced as default disabled. But ASCII encoding is a desired default behavior, so from V16 it will be default enabled.

Notice that:

1. Existing media file names will not be affected - they will remain as-is after upgrading to V16.
2. The current behavior of "default char replacements" (via the configuration option RequestHandler:EnableDefaultCharReplacements) will not be impacted by this change.

Version

Umbraco 16

Previous behavior

Media file names was not ASCII encoded by default.

New behavior

Media file names will be ASCII encoded by default.

Type of breaking change

• Binary incompatible: Existing binaries may encounter a breaking change in behavior, such as failure to load/execute or different run-time behavior.
• Source incompatible: Source code may encounter a breaking change in behavior when targeting the new runtime/component/SDK, such as compile errors or different run-time behavior.

Reason for change

ASCII encoding media file names by default will increase consistency between the generated document and media URLs.

Recommended action

To avoid ASCII encoded media file names, use the configuration option RequestHandler:ConvertFileNamesToAscii to disable this feature.

Affected APIs

None.