[IntelliCode for C# Dev Kit] Add API Usage Examples

[TintedKiwi]

Please add API Usage Examples functionality to the IntelliCode for C# Dev Kit extension.

Visual Studio has this functionality for quite a while now:

On VSCode, the IntelliCode API Usage Examples extension provides this functionality for Python, JavaScript and TypeScript:

Currently, the IntelliCode for C# Dev Kit extension does not have it:

[773704476]

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