Quick/Bulk Edit: Pass post to quick edit custom hook

[ArkaPrabhaChowdhury]

This addresses #53195 by rendering the quick_edit_custom_box fields after the selected post ID is known.

Quick Edit initially renders a hidden template that is cloned in JavaScript. The patch adds an authenticated inline-edit-custom-box AJAX request when a post is opened. The request loads the post, checks the nonce and edit capability, invokes quick_edit_custom_box with the actual WP_Post object as its fourth argument, and injects the response into the cloned editor.

Trac ticket: https://core.trac.wordpress.org/ticket/53195

Testing

• Focused PHPUnit test: 1 test, 3 assertions passed using the Local by Flywheel wordpress-develop PHP/MySQL runtime.
• PHPCS: 0 errors; 2 existing baseline warnings in unchanged code at class-wp-posts-list-table.php lines 97 and 123.
• PHPCBF: no fixable errors.
• PHP lint passed for all changed PHP files.
• JavaScript lint passed for src/js/_enqueues/admin/inline-edit-post.js.
• git diff --check passed.

Use of AI Tools

AI assistance: Yes
Tool(s): ChatGPT/Codex
Model(s): GPT-5
Used for: Implementation, test coverage, and validation; the final patch and test results were reviewed before submission.

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