Support debug/createConfiguration proposed menu API

[rschnekenbu]

What it does

This PR adds the support of the newly introduced debug/createConfiguration menu. This menu is currently a proposed API.

fixes #14114

contributed on behalf of STMicroelectronics

How to test

A test extension has been developed to test this feature:

• src: scm-menu-sample-0.0.3-src.zip
• zipped vsix: scm-menu-sample-0.0.3.zip

The steps to reproduce are almost the same as in VS code:

• delete the launch.json file from your .theia/.code folder
• Go to the debug view and click on the cog wheel that opens or create the launch.json file.
• if the extension is not installed, the behavior should be the same as usual, e.g. generate a skeleton of launch.json and edit it.
• if the extension is installed, some quick pick menu shall come, that allows you to select between the available commands from the new menu or the usual launch.json generation and edition.
• The command, once invoked, does not do anything currently except showing a notification. It would be up to the extension to generate a file as far as I understand the feature on vs code.

https://github.com/user-attachments/assets/ec99fa6b-48bf-4bfc-863f-8d1b8a940de4

Follow-ups

None

Review checklist

• [ ] As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines