test: migrate playgrounds to ESM

[fi3ework]

Description

A successor of #8252 and #12131. This PR mainly contains the following changes.

• adding "type": "module for most packages in /playground except the ones for testing in CJS, they're:
  • playground/cli/package.json
  • playground/css-codesplit-cjs/package.json:
  • playground/define/commonjs-dep/package.json
  • playground/resolve/exports-and-nested-scope/package.json
  • playground/resolve/exports-with-module/package.json
  • playground/resolve-config/package.json
  • playground/ssr-noexternal/require-external-cjs/package.json
• changed some test cases from .mjs -> .js due to type: module toggling the dist artifacts ext.
• remove playground/hmr/tsconfig.json which is no longer useful.
• found an orphan test file (playground/json/server.js) from fix(ssr): avoid transforming json file in ssrTransform #6597. The file is not invoked because that PR merged after /packages/playground/json moves to /playground/json and becomes ineffective in rebasing. The weird thing is that I didn't see added new test case in fix(ssr): avoid transforming json file in ssrTransform #6597(Did I miss something 🤔?). So I tried to add some basic test cases for it. And I leave some // TODO: what is this for? on some lines I don't understand clearly.
• adding import/no-commonjs for playground with some excluded CJS fixtures to keep using ESM afterward.

Additional context

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

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[fi3ework]

@poyoho Could take a look at https://github.com/vitejs/vite/pull/13094/files#diff-1ce4192bd1beda65d5cd5385762abd35e0b9c82cce09f4198d8d259df423a6c4 in case I missed some test intention in #6597.

[poyoho]

The test will test the large json file in ssr bundle with esm would not to out of max timeline.

[fi3ework]

The test will test the large json file in ssr bundle with esm would not to out of max timeline.

@poyoho So I guess we do not need to test the metrics result of the line under // TODO: what is this for?. Is it for local debugging only? 🤔

vite/playground/json/index.ssr.html

Lines 15 to 21 in 54c023b

	// TODO: what is this for?
	text('.fetch-json-module code', Date.now() - startModule)
	const startFs = Date.now()
	text('.fetch-json-fs pre', await (await fetch('/json-fs')).text())
	// TODO: what is this for?
	text('.fetch-json-fs code', Date.now() - startFs)

[bluwy]

Thanks for migrating these once again! Left some comments below, mostly nitpicks.

[bluwy]

Looks great! 🔥