Title: Restore Devart Code Compare support #979

Feature request

I'd like to request reinstating Devart Code Compare as a supported diff tool in DiffEngine.

Code Compare was previously supported but removed in [PR #370](#370) on July 9, 2023, because it had reportedly not been updated since 2020.

That reason is no longer applicable. Devart has since released several updates:

• 5.4.20 (May 2024): Visual Studio 2022 support.
• 5.4.27 (August 2024): Bug fixes and improvements.
• 5.5.11 (March 2026): Visual Studio 2026 support and an x64 stability fix.

[Official revision history](https://www.devart.com/codecompare/revision_history.html)

Requested implementation

Restore the previous integration, including:

• DiffTool.CodeCompare enum entry.
• Automatic detection of CodeCompare.exe in standard installation directories.
• Support for custom executable locations.
• Two-file comparisons using the existing command-line interface.
• Support for selecting Code Compare using DiffTools.UseOrder(DiffTool.CodeCompare).

The original implementation can be recovered from PR #370, potentially with minimal changes.

Devart continues to document its [command-line interface](https://docs.devart.com/code-compare/using-command-line/comparing-via-command-line.html), including support for standalone and Visual Studio-integrated comparison windows.

Motivation

Code Compare offers several useful capabilities for reviewing C# and other source files, including code folding, collapsing unchanged regions, moved-block detection, and similar-code-line detection.

I'd like to use these capabilities when reviewing Verify snapshot differences without having to manually open the compared files.

Given that Code Compare is actively maintained again and the previous integration already exists in Git history, would you consider restoring support?