Docker: chown WordPress install to web user so wp-admin updates work

[DevinWalker]

Fixes MONOREP-406

Proposed changes

• Add chown -R "$user:$group" /var/www/html to tools/docker/bin/run.sh just before Apache starts.
• Provisioning steps in run.sh (wp core download, wp config set, the plugin symlinks loop, etc.) all run as root, but Apache subsequently runs as www-data. Without a chown step, the WordPress install stays owned by root:root and the auto-updater fails with files_not_writable. From the user's side this shows up as:
  • The An automated WordPress update has failed to complete - please attempt the update again now. admin notice.
  • Every plugin / theme / core update from wp-admin failing silently or with a generic error.
  • wp core update succeeding only when run as root via docker exec -u root, never via the normal admin flow.
• The chown is intentionally unconditional (every container start, not just first-install), so existing environments provisioned before this fix self-heal on the next jetpack docker up — no manual chown required by anyone hitting this today.

Related product discussion/links

• Surfaced while diagnosing a developer's Docker env where wp-admin had been showing the failed-update notice for weeks and core was pinned at 7.0-beta2-61800 because nothing could overwrite the existing files. Setup workflow referenced: PCYsg-GJ2-p2.
• Adjacent gap (not addressed here): jetpack docker update-core was announced on +jetpackdevelopment in Feb 2025 but is still undocumented in tools/docker/README.md — separate doc PR could follow.

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

No — local dev environment script only.

Testing instructions

1. Start fresh: jetpack docker clean && jetpack docker up -d (or just jetpack docker down && jetpack docker up -d against an existing install that's currently broken).
2. Once the WordPress container is up, verify ownership inside the container:

   docker exec jetpack_dev-wordpress-1 stat -c '%U:%G' /var/www/html/wp-includes/version.php
   

   Expected: www-data:www-data (previously: root:root).
3. Visit wp-admin. If a previously-installed environment had been showing "An automated WordPress update has failed to complete - please attempt the update again now", that notice should be gone (or clear after the next update check).
4. From wp-admin → Dashboard → Updates, click Update to latest version (or run jetpack docker wp core update). It should succeed instead of files_not_writable.
5. Same for jetpack docker wp plugin update --all and jetpack docker wp theme update --all.
6. (Optional sanity check) On the host: ls -la tools/docker/wordpress/wp-includes/version.php — Docker Desktop's user namespacing should still present the file as readable from the host.

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[tbradsha]

While I suspect this shouldn't cause any issues...

I haven't yet checked out your branch, and everything is root:root on my end, but I'm not able to reproduce the reported issue; updates to plugins/themes work fine for me. Do you have more context on the failing setup?

As for updating core, I can confirm it also worked for me. That said, I recommend instead using jetpack docker update-core (which runs tools/docker/bin/update-core.sh in the env), as otherwise tests that run on Docker risk having mismatched core PHPUnit tests, which have been known to break things.

cc: @anomiex in case I missed some nuance here.