Heartbeat: move site environment stats to Connection package

[bindlegirl]

Fixes CONNECT-167

Proposed changes

Follow-up to #46967 and #49922. This completes the heartbeat-stats audit by moving the generic site environment stats out of the Jetpack plugin and into the Connection package, so they're reported for every connected site (including standalone-connection installs).

• Add Automattic\Jetpack\Heartbeat::get_environment_stats() to the Connection package, generating: wp-version, php-version, wp-branch, php-branch, public, ssl, is-https, language, charset, is-multisite, plugins, mu-plugins, space-used, is-multi-network, ip-2-octets.
• Port permit_ssl() (for the ssl stat) and get_active_plugins() (for the plugins stat) into the package, and use Status::is_multi_network() for is-multi-network. The ported permit_ssl() shares the jetpack_https_test transient with the plugin's copy to avoid duplicate network checks.
• Manager::add_stats_to_heartbeat() now merges the environment stats (gated on connection, as before).
• The Jetpack plugin's Jetpack_Heartbeat::generate_stats_array() now only returns plugin-specific stats (version, branch, manage-enabled, module-*).
• Refactor the plugin's local consumers so their output is unchanged: Jetpack::get_stat_data() (WPCOM sync) and Jetpack::jetpack_check_heartbeat_data() (wp jetpack status full) now merge the environment stats from the Connection package.
• Add Heartbeat_Test coverage and extend the Manager heartbeat tests.

Stats intentionally left in the Jetpack plugin

version / branch (JETPACK__VERSION), manage-enabled, and module-* are Jetpack-plugin-specific and stay in the plugin's heartbeat contribution.

Related product discussion/links

• CONNECT-167
• Follow-up to IDC: move heartbeat stat to connection package #46967 and Heartbeat: move connection-related stats to Connection package #49922

Does this pull request change what data or activity we track or use?

No new data is collected. The same environment stats are still sent; they now originate from the Connection heartbeat instead of the Jetpack plugin. As a side effect, standalone-connection sites (a connection but no Jetpack plugin) will now report these environment stats. They are still only sent for connected sites. WPCOM sync stat data (get_stat_data) and the wp jetpack status full output are unchanged.

Testing instructions

• Code review.
• On a connected site, trigger jetpack_v2_heartbeat (e.g. via the Crontrol plugin) and confirm the environment stats (wp-version, php-version, ssl, plugins, etc.) are part of the heartbeat received on WPCOM, matching the previous behavior.
• Run wp jetpack status full and confirm wp-version / php-version are still listed/flagged correctly.
• jetpack test php packages/connection passes (includes new Heartbeat_Test coverage).

[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 or WordPress.com Site Helper), and enable the update/heartbeat-env-stats-to-package branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack update/heartbeat-env-stats-to-package

bin/jetpack-downloader test jetpack-mu-wpcom-plugin update/heartbeat-env-stats-to-package

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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[jp-launch-control]

Code Coverage Summary

Coverage changed in 3 files.

File	Coverage	Δ%	Δ Uncovered
projects/packages/connection/src/class-heartbeat.php	71/129 (55.04%)	3.09%	21 💔
projects/packages/connection/src/class-manager.php	689/1032 (66.76%)	0.03%	0 💚
projects/plugins/jetpack/class.jetpack-heartbeat.php	12/16 (75.00%)	-5.95%	-4 💚

Full summary · PHP report · JS report

_{If appropriate, add one of these labels to override the failing coverage check: Covered by non-unit tests Use to ignore the Code coverage requirement check when E2Es or other non-unit tests cover the code Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage.}