What?

Follow up to #73120 and #73137.

The @wordpress/build page templates generate PHP files (output under wp-includes/build/pages/…) that invoke action hooks. This PR brings those hooks in line with the WordPress PHP documentation standards:

• Add a DocBlock for the per-page init action ({page_slug}_init in page.php.template, {page_slug}-wp-admin_init in page-wp-admin.php.template), which previously had only a // line comment.
• Replace the duplicated copies of core hook DocBlocks (admin_head, admin_head-{$hook_suffix}, admin_footer, admin_footer-{$hook_suffix}) in page.php.template with the standard /** This action is documented in … */ reference comments.

No behavior changes — documentation only.

Why?

Every action and filter should be documented, either with an inline DocBlock or, when the hook is documented elsewhere, with a This action/filter is documented in <file> reference comment. The page templates currently fall short in two ways:

1. The init actions are undocumented. {page_slug}_init / {page_slug}-wp-admin_init carry only a // Fire init action… line comment, so every generated page ships an undocumented hook.
2. Core hook DocBlocks are duplicated. The admin-header/admin-footer emulation region copies core's DocBlocks for admin_head, admin_footer, and their -{$hook_suffix} variants verbatim. These hooks are defined and documented in wp-admin/admin-header.php and wp-admin/admin-footer.php; core itself never duplicates a hook's DocBlock and instead uses the "documented in" reference. Duplicating risks the copies drifting from the canonical documentation and misrepresents where the hooks are defined.

(For context, a PHPStan rule being added on the WordPress core side flags exactly these two patterns, which is how they surfaced.)

How?

• Added a DocBlock above the init do_action() in both page templates. No @since is included: a single shared template generates pages introduced in different versions, so no single version would be correct for the substituted hook name.
• Replaced the four duplicated core DocBlocks in page.php.template with /** This action is documented in wp-admin/admin-header.php */ and /** This action is documented in wp-admin/admin-footer.php */ as appropriate.
• Left the {page_slug}_boot_dependencies filter's DocBlock untouched — it is a genuinely new, page-specific filter (not a re-fire of a core hook), so its inline DocBlock is the canonical documentation and is correct as-is.

Testing Instructions

This is a documentation-only change to the build templates; there is no runtime behavior change.

1. Run a production build: npm run build.
2. Inspect a generated page, e.g. build/pages/font-library/page.php:
   • The init do_action( 'font-library_init' ) is now preceded by a /** … */ DocBlock.
   • The admin_head, admin_head-{$hook_suffix}, admin_footer, and admin_footer-{$hook_suffix} calls are now preceded by /** This action is documented in … */ reference comments instead of copied DocBlocks.
3. Inspect a wp-admin page, e.g. build/pages/.../page-wp-admin.php, and confirm the …-wp-admin_init action now has a DocBlock.

Testing Instructions for Keyboard

N/A — no UI changes.

Screenshots or screencast

N/A — documentation-only change to generated PHP.

Use of AI Tools

This pull request was authored with the assistance of Claude Code (Claude Opus). All changes were reviewed by the contributor, who takes responsibility for them.