fix(config): watch envDir even outside of root

[fi3ework]

Description

a repro: https://stackblitz.com/edit/vitejs-vite-ux3kxh?file=.env. Modify .env and the server will not restart (Ideally it should).

When envDir is out of resolvedConfig.root, it won't be watched.

Additional context

Annotate envDir as an internal field as it's not required by user so far (I guess :P)
And, I belileve after this PR, we have watched all the things that could trigger a server restart.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[bluwy]

I think it's safe enough to not need to make this internal. Currently, ResolvedConfig has envDir?: string | undefined, this would make a previous public API internal, which is sort-of a breaking change.

Removing the /** @internal */ comment should be good.

Suggested change

	/** @internal */
	envDir: string
	envDir: string

[fi3ework]

Updated. nice catch. I feel even more that we need some type checking (maybe leverage tsd). I'll give it a try.