Provide document links in tsconfig/jsconfig files

[mjbvz]

VS Code includes some very basic support for IntelliSense in tsconfig/jsconfig files. This includes providing document links for extends, files, and references in these files:

This currently requires a fair amount of code in the VS Code extension and there are bugs (for example microsoft/vscode#276592) that would require a lot more code to address

I'd love to have this logic be handled by typescript directly so that it matches exactly how tsc / ts-go works. Other editors could then also benefit from it

[jakebailey]

We could do this, though it would require us to be equipped to handle JSON files.

In the client, we can add the right patterns to the document selector to avoid the client sending us so many JSON files, e.g. the API's example of:

let sel: DocumentSelector = [{ language: 'typescript' }, { language: 'json', pattern: '**∕tsconfig.json' }]`;

Which I believe VS Code handles like:

	const patterns: vscode.GlobPattern[] = [
		'**/[jt]sconfig.json',
		'**/[jt]sconfig.*.json',
	];

https://github.com/microsoft/vscode/blob/main/extensions/typescript-language-features/src/languageFeatures/tsconfig.ts