Activity Log abilities: register events reads via Registrar

[enejb]

Summary

Registers the jetpack-activity-log/list-events ability via the WordPress Abilities API so AI agents can answer "what happened on my site?" through the standard wp-abilities/v1 REST surface. Single consolidated read — passing event_id returns a 0- or 1-element array, so the same ability covers both list and detail views (per plan §4.2's "consolidated-read" guidance).

• New Activity_Log_Abilities Registrar subclass under Automattic\Jetpack\Activity_Log\Abilities, namespaced category slug jetpack-activity-log.
• Delegates to REST_Controller::get_activity_log() so the ability rides on the existing permission check, free-tier clamp, and WPCOM proxy path — no duplicate auth surface.
• Wired via the canonical guarded actions.php pattern (autoload-files); gated behind the default-off jetpack_wp_abilities_enabled filter inside Registrar::init(), so it stays opt-in per-site until the flag is flipped.
• Filters supported: group, action, date_from / date_to (ISO8601), page, per_page (max 100), event_id. action and event_id are applied client-side after the proxy returns (they're not part of the upstream /jetpack/v4/activity-log query surface).

Test plan

• Unit tests pass: composer phpunit -- --filter Activity_Log_Abilities_Test (25 tests / 72 assertions, no notices).
• PHPCS clean across src/abilities/, tests/php/, and actions.php.
• Permission gate denies subscribers, anonymous, and admins without a user-level Jetpack connection (mirrors REST_Controller::permissions_callback()).
• Consolidated-read contract: unknown event_id returns [] (not WP_Error); known event_id returns a 1-element projected array.
• Input mapping: date_from → after, date_to → before, per_page → number (clamped to 100), group → single-element array. Verified via captured WP_REST_Request.
• Upstream WP_Error propagates unchanged.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the add/ship-activity-log-abilities branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/ship-activity-log-abilities

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

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Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen as soon as you deploy your changes after merging this PR (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly:
  • Scheduled release: June 2, 2026
  • Code freeze: June 1, 2026

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/class.jetpack.php	748/2277 (32.85%)	-0.01%	1 ❤️‍🩹

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