Add URL Details endpoint from Gutenberg plugin into Core

[hellofromTonya]

Adds the new URL Details endpoint to the REST API to allow retrieval of information about a remote URL.

• WP_REST_URL_Details_Controller ​https://github.com/WordPress/gutenberg/blob/trunk/lib/class-wp-rest-url-details-controller.php
• WP_REST_URL_Details_Controller_Test ​https://github.com/WordPress/gutenberg/blob/trunk/phpunit/class-wp-rest-url-details-controller-test.php

Tests and code will need adjustment for newer changes in 5.9 including tests and PHP 8.1.

Ports the URL Details from the Gutenberg repo to Core.

Updates the code to the newest changes in Core including: tests, PHP 8.1, standards, etc.

Trac ticket: https://core.trac.wordpress.org/ticket/54358

Hey @TimothyBJacobs, If you get time, could you please do a confidence check review as @getdave is on holiday?

This looks great to me!

[hellofromTonya]

In 51973:

REST API: Add URL Details endpoint.

Adds a new REST API endpoint (/wp-block-editor/v1/url-details) for retrieving information from an external URL.

Information retrieved:

• Title: content of the <title> element
• Icon: favicon image link
• Description: content of the description or og:description meta element
• Image: OG image link

This endpoint is used by the block editor for link previews.

Props get_dave, aduth, andraganescu, beaulebens, hellofromTonya, kevin940726, mamaduka, marekhrabe, mnelson4, noisysocks, obenland, ocean90, retrofox, shaunandrews, spacedmonkey, swissspidy, timothyblynjacobs, xknown, youknowriad.
Fixes #54358.

[swissspidy]

The translatable strings added in [51973] should use sprintf with placeholders instead of containg HTML tags correctly.

e.g. The OG image link of the <meta property="og:image"> or <meta property="og:image:url"> element from the URL. should really be The OG image link of the %1$s or %2$s element from the URL.. The placeholders can be explained in a translators comment.

Also, translators don't necessarily know what "OG" is. Maybe use "Open Graph image link" instead of "OG image link", or just "image link"?

Committed via changeset https://core.trac.wordpress.org/changeset/51973.

[swissspidy]

Also, filters like rest_prepare_url_details need @since annotations.

[hellofromTonya]

Thank you @swissspidy! I'll create a follow-up patch shortly with those changes.

[swissspidy]

The $remote_url_response of the rest_prepare_url_details filter is described as an array, but is a string.

Follow-up to changeset https://core.trac.wordpress.org/changeset/51973 to improve:

• Translations by removing HTML tags and spelling out OG
• Adding @since param to new filters
• Improving comments for code standards and consistency
• Improving readability by making multiple args multiline
• Micro-optimizations to avoid unnecessary variable assignments

Trac ticket: https://core.trac.wordpress.org/ticket/54358

@swissspidy This PR addresses the code review improvements you mentioned in the ticket. Could you please review the PR? Thanks!

Thank you @swissspidy!

Hey @SergeyBiryukov, Could you please review the PR? Thanks!

[hellofromTonya]

In 52008:

REST API: Improve translations, comments, and readability in URL Details endpoint.

Improvements:

• Removes HTML tags from translatable strings. Uses sprintf with placeholder and translators comment.
• Spells out "OG" to "Open Graph" to help translators.
• Adds @since param to new filters.
• Improves comments for code standards and consistency.
• Improves readability by making multiple args multiline.
• Micro-optimizations to avoid unnecessary variable assignments.

Follow-up to [51973].

Props hellofromTonya, sergeybiryukov, swissspidy.
Fixes #54358.

Committed via changeset https://core.trac.wordpress.org/changeset/52008.

Thank you @hellofromtonya 🙇