fix!: move certain types to import them from @eslint/markdown/types

[lumirlumir]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request?

Hello.

The purpose of this PR is to align the type import path with the JSON and CSS plugins.

This is a breaking change, and it was discussed in #367 (comment) Also, it serves as a prerequisite for #367.

Currently, we import *RuleDefinition and *RuleVisitor types directly from the main entry point, like @eslint/markdown.
This PR moves those types under @eslint/markdown/types.

Here are some references:

• https://github.com/eslint/json/blob/main/tests/types/types.test.ts#L3-L7
• https://github.com/eslint/css/blob/main/tests/types/types.test.ts#L55

Looking at the dist folders of the JSON and CSS plugins, they do not export *RuleDefinition and *RuleVisitor types from their main entries (e.g., @eslint/json, @eslint/css).
Instead, they export those types from @eslint/json/types and @eslint/css/types, respectively.

---

One thing I'm unsure about is how we should handle the RuleModule type in the Markdown plugin.
I've left a detailed comment regarding this concern.

What changes did you make? (Give an overview)

Related Issues

Ref: #367 (comment)

Is there anything you'd like reviewers to focus on?

[lumirlumir]

Suggested change

	/** @typedef {import("./types.ts").MarkdownRuleDefinition} RuleModule */
	/** @typedef {import("./types.ts").MarkdownRuleDefinition} RuleModule */

I'm not sure whether we should remove the RuleModule type or not.

This RuleModule type was originally introduced in #333 to align with the current Rule.RuleModule implementation in eslint:

• https://github.com/eslint/eslint/blob/eaf8a418af32b3190494e4a2284533353c28ccfa/lib/types/index.d.ts#L595-L606

However, a notable point is that the RuleModule type does not exist in the JSON or CSS plugins.

So, I think a decision from @eslint/eslint-tsc is needed on whether we should retain the RuleModule type in @eslint/markdown or not.

[fasttime]

This RuleModule type was originally introduced in #333 to align with the current Rule.RuleModule implementation in eslint

It looks like that type was already exported before #333. I can trace it back to @eslint/markdown v6.0.0:

https://github.com/eslint/markdown/blob/v6.0.0/src/index.js#L22

It was later changed to match the definition of MarkdownRuleDefinition in #324.

However, a notable point is that the RuleModule type does not exist in the JSON or CSS plugins.

So, I think a decision from @eslint/eslint-tsc is needed on whether we should retain the RuleModule type in @eslint/markdown or not.

Since we are going to have a major release, I think it's the right time to remove RuleModule 👍

[lumirlumir]

Sounds good to me 👍

I'll remove the RuleModule type and the related test cases once #367 is merged.

[lumirlumir]

Suggested change

	type RuleModule,
	type RuleModule,

Same with #446 (comment)

[lumirlumir]

I've removed the RuleModule type and the related test cases, referencing the JSON test implementation 👍

[nzakas]

LGTM. Would like @fasttime to review before merging.

[fasttime]

LGTM, thanks!