Expose `textChanges.ChangeTracker` for public API

Suggestion

I'm not sure how such requests as this one suits into TypeScript repo, but I've seen such requests earlier so decided to put another one!

Motivation: Currently it's very unclear for new developers how to contribute new code actions (refactorings / quick fixes: getEditsForRefactor / getCodeFixesAtPosition) with current plugins API. While factory API is exposed AFAICS the only way to convert nodes to actual changes is ts.createPrinter().printNode, which makes passed in formatOptions useless (just always inserting semicolons is already too annoying). I don't see a reason why don't let other developers to build their own code actions in the same way as built-in bulit.

Of course I've already seen a lot of plugins using in our days, most of them are using constructor and with along with these methods: insertNodeAt, replaceNodeRange, delete and a few others. With types exposed it would be easier to use language service methods that receive formatOptions.

🔍 Search Terms

Language Service Plugins API

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✅ Viability Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

⭐ Suggestion

📃 Motivating Example

💻 Use Cases

まず、issue で示されている language service plugin のエントリポイント、特に getEditsForRefactor と getCodeFixesAtPosition を、textChanges.ChangeTracker およびその insertNodeAt、replaceNodeRange、delete メソッドと併せて読みます。ChangeTracker を公開するための public API と互換性要件を、formatOptions をどのように使用するかも含めて確認します。対応するサーフェスと検証方針が明確になれば完了です。