fix(post-date): use block bindings instead of deprecated displayType

[rbcorrales]

All Submissions:

• Have you followed the Newspack Contributing guideline?
• Does your code follow the WordPress' coding standards and VIP Go coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

Follow-up to #428. Updates all 5 post-meta patterns to use the modern WordPress Block Bindings API for the modified date block instead of the deprecated displayType attribute.

Before: <!-- wp:post-date {"displayType":"modified"} /-->
After: <!-- wp:post-date {"metadata":{"bindings":{"datetime":{"source":"core/post-data","args":{"field":"modified"}}}},"className":"wp-block-post-date__modified-date"} /-->

The displayType attribute was superseded by Block Bindings in WordPress/gutenberg#70585. WordPress still renders it via a legacy fallback, but the attribute is no longer in the block schema and the editor UI doesn't recognize it as the "Modified Date" variation.

The wp-block-post-date__modified-date CSS class is included for styling and detection purposes.

Closes NPPD-1278.

How to test the changes in this Pull Request:

1. Activate the Newspack Block Theme and enable "Show last updated date" in the plugin settings.
2. Reset the Single Posts template (Site Editor > Templates > Single Posts > Actions > Reset).
3. View a post modified well after publication. Verify both dates render correctly.
4. Open the Single Posts template in the Site Editor. Verify the modified date block shows as "Modified Date" in the block toolbar (not just "Post Date").
5. Verify the rendered HTML includes the wp-block-post-date__modified-date class on the modified date block.

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?

[Copilot]

Pull request overview

Updates the theme’s post-meta block patterns to represent “Modified Date” using the WordPress Block Bindings API (instead of the deprecated displayType attribute), aligning the patterns with modern core block schema/UI behavior.

Changes:

• Replaces core/post-date’s deprecated displayType:"modified" attribute with metadata.bindings pointing datetime to core/post-data field modified.
• Adds wp-block-post-date__modified-date class to the modified-date core/post-date blocks for styling/detection consistency.
• Applies the update across all 5 post-meta patterns.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
patterns/post-meta/post-meta-single-line.php	Updates modified date block to use block bindings + adds modified-date class.
patterns/post-meta/post-meta-single-line-avatar.php	Same binding/class update for the single-line avatar variant.
patterns/post-meta/post-meta-multiple-lines.php	Same binding/class update for the multiple-lines variant (with date format preserved).
patterns/post-meta/post-meta-multiple-lines-avatar.php	Same binding/class update for the multiple-lines avatar variant (with date format preserved).
patterns/post-meta/post-meta-compact.php	Same binding/class update for the compact variant (with font size preserved).

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[laurelfulford]

Looks good, @rbcorrales! 🙌

[github-actions]

🎉 This PR is included in version 1.28.0-alpha.1 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀