feat: Pass --max-warnings value to formatters

[btmills]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request? (put an "X" next to an item)

[ ] Documentation update
[ ] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofix to a rule
[ ] Add a CLI option
[x] Add something to the core
[ ] Other, please explain:

What changes did you make? (Give an overview)

This fixes #14881 by giving formatters access to the --max-warnings threshold when it is exceeded. The maxWarningsExceeded property matches what stylelint uses.

I had hoped to disable ESLint's own output message if the formatter provides its own message, but that would require even more API, so that's left as a future possibility if we get a request for it.

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

1. The logic lives in the CLI's execute() method because that's where we're already doing the tooManyWarnings exit code calculation. We could instead pass the maxWarnings threshold through to ESLint/FlatESLint and have them replicate that calculation to create the maxWarningsExceeded object, but that seemed worse. I tested this logic as part of the CLI's formatter tests rather than the --max-warnings tests, though the logic is adjacent.
2. Rather than adding a maxWarningsExceeded arg and piping that through, I put it in a resultsMeta object in case we want to add something else to it in the future.
3. stylelint's maxWarningsExceeded property only exists if the threshold was exceeded. We could set it to null or false instead of omitting it, but I matched stylelint's behavior.
4. I enabled this for both ESLint as well as FlatESLint because I only had to pass through the resultsMeta object. If we feel like we need more carrots to encourage switching to FlatESLint and that this would be a good one, I could remove it.

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[mdjermanovic]

LGTM, thanks!

[fasttime]

I would suggest to update the definition of LoadedFormatter to include the new resultsMeta argument:

eslint/lib/eslint/eslint.js

Lines 40 to 44 in 2dc338a

	/**
	* The main formatter object.
	* @typedef LoadedFormatter
	* @property {function(LintResult[]): string | Promise<string>} format format function.
	*/

The definition of FormatterFunction could use an update with the maxWarningsExceeded property:

eslint/lib/shared/types.js

Lines 193 to 199 in 2dc338a

	/**
	* A formatter function.
	* @callback FormatterFunction
	* @param {LintResult[]} results The list of linting results.
	* @param {{cwd: string, rulesMeta: Record<string, RuleMeta>}} [context] A context object.
	* @returns {string | Promise<string>} Formatted text.
	*/

[fasttime]

- The object has two properties:
+ The object has two or three properties:

or maybe just "the following properties"?

[btmills]

Thanks for catching this! Fixed in c772b6c.

[btmills]

I updated the typedefs in 5624b0b; see that commit message for more details, including why I'll be doing a follow-up PR to further improve formatter typedefs as used by FlatESLint.

[fasttime]

Thanks @btmills! Nice work 👍🏻

[mdjermanovic]

LGTM, thanks!