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

首先阅读 issue 中提到的 language service plugin 入口点，尤其是 getEditsForRefactor 和 getCodeFixesAtPosition，同时阅读 textChanges.ChangeTracker 及其 insertNodeAt、replaceNodeRange 和 delete 方法。确定公开 ChangeTracker 所需的 public API 和兼容性要求，包括 formatOptions 的使用方式；当受支持的 surface 和验证方法明确后即算完成。