Build: update changelog

[simison]

What?

Adds missing changelog entries to WP Build for past two versions.

Follow-up to PRs:

• wp-build: Fix black flash on wp-admin pages before hydration #78493
• Script Loader: Defer single-page admin init until DOMContentLoaded (Trac #65103) #78136
• wp-build: Replace getter-based exports with data properties #78303
• Fix: Guard require_once calls in generated PHP files against deployment race conditions #78110

I'm leaving out any experimental dashboard "widget" additions to build, since those are experimental and not really encouraged yet for use. They're documented here.

See changelog for widget PRs just for awareness

0.15.0 (2026-05-27)

Enhancements

• Add presentation field support to widget.json for declarative full-bleed rendering (#78209).
• Add content-bleed presentation variant for widgets that keep their header but render edge-to-edge content (#78491).

Documentation

• Document that widget icons must be SVGs, not dashicons (#78440).
• Document optional widget package.json and add widgets/tsconfig.json for TypeScript (#78467).

0.14.0 (2026-05-14)

New Features

• Add experimental widgets/ folder support for discovering, bundling, and registering dashboard widget script modules (#77347).

Enhancements

• Bootstrap the widget type registry into generated admin pages and add widget modules to the page import map (#77917).
• Decouple generated page templates from widget type registration so pages remain widget-agnostic (#77958).
• Expose registered widget types to admin pages via the REST API and core-data instead of inline globals (#77987).

Why?

WP Build is harder to version bump in plugins when there isn't a clear changelog.

How?

AI pulled summaries for merged PRs that didn't add a changelog entry.

Use of AI Tools

yes

[github-actions]

Flaky tests detected in 512b4d8.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/26632338477
📝 Reported issues:

• [Flaky Test] Should save the changes #78689 in /test/e2e/specs/editor/plugins/wp-editor-meta-box.spec.js

[jsnajdr]

nice 👍

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

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Co-authored-by: simison <simison@git.wordpress.org>
Co-authored-by: jsnajdr <jsnajdr@git.wordpress.org>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

[aduth]

I generalized the GitHub Actions check-package-changelogs.yml recently in #78169 so we could add more packages like this if we wanted a stronger nudge to write changelogs for this package. And/or adding package-specific AGENTS.md to encourage AI agents to write it (as in #78166).