[FEATURE]: Add VS Code Insiders to "Open in" app list #14412

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

I'd like to add support for opening projects with VS Code Insiders from the desktop app "Open in" menu.

Problem

The current menu includes VS Code, Cursor, Zed, etc., but not VS Code Insiders.

Proposed change

Add a new option:

• Label: VS Code Insiders
• macOS openWith: Visual Studio Code - Insiders
• Windows/Linux openWith: code-insiders
• Reuse existing VS Code icon initially

Why this helps

Many users run Insiders as their primary editor and expect parity with the existing "Open in" options.

I can open a PR for this change after feedback.