Add name to wp_register_webfonts

[simison]

What?

Solves #46398

Adds support for name attribute in wp_register_webfonts:

array(
	'name'         => 'Example (Japanese)',
	'font-family'  => 'Example',

	'font-style'   => 'normal',
	'font-weight'  => '200 900',
	'font-stretch' => 'normal',
	'src'          => 'https://example.com/assets/fonts/source-serif-pro/SourceSerif4Variable-Roman.ttf.woff2',
	'font-display' => 'fallback',
	'provider'     => 'local',
)

Why?

I'm describing use case in detail at #46398, but essentially to match how theme.json already works.

How?

Allows passing name attribute as part of font family array.

I'm not entirely happy with solution as conceptually "Name" would belong to higher up, not necessarily inside font-family definition. I also didn't see better alternative.

Testing Instructions

Add this to mu-plugins or elsewhere:

function register_example_font() {
	$font_family = "Example";
	$font_name = "Example (Japanese)";
	
	wp_register_webfonts(
		array(
			array(
				'provider'     => 'local',
				'name'         => $font_name,
				'font-family'  => $font_family,
				'font-style'   => 'normal',
				'font-weight'  => '200 900',
				'font-stretch' => 'normal',
				'src'          => 'https://example.com/assets/fonts/source-serif-pro/SourceSerif4Variable-Roman.ttf.woff2',
				'font-display' => 'fallback',
			),
			array(
				'provider'     => 'local',
				'name'         => $font_name,
				'font-family'  => $font_family,
				'font-style'   => 'italic',
				'font-weight'  => '200 900',
				'font-stretch' => 'normal',
				'src'          => 'https://example.com/assets/fonts/source-serif-pro/SourceSerif4Variable-Italic.ttf.woff2',
				'font-display' => 'fallback',
			),
		)
	);
}
add_filter( 'init', 'register_example_font' );

Open site editor and note font families:

Testing Instructions for Keyboard

Screenshots or screencast

[hellofromtonya]

Block this PR until the architectural redesign is completed and merged. (See my comment here #46398 (comment) for more context.) Once merged, then can revisit what changes are needed in this PR, if any.

[hellofromtonya]

This PR is now unblocked. It will need to be rebased and rebuilt to apply the enhancement to the newly designed Fonts API (which is now in trunk). Please note, the API has a brand new architecture and was renamed (including all of the files, functions, classes, tests, etc.).

[hellofromtonya]

This PR was applied to the old API. It will not work with the new API. I think it's best to close this PR, but use it as reference for the intent. Then open a new PR to add the enhancement to the new API.