Add automatic WordPress.org plugin repository deployment

[Copilot]

On every versioned tag push, the plugin should be automatically published to the WordPress.org plugin repository in addition to creating a GitHub release.

Changes

• .distignore — new file consumed by the deploy action to exclude dev-only files from the SVN commit (.github, composer.json, composer.lock, .wp-env.json, etc.)
• release-plugin.yml — adds a deploy job that runs after the existing release job, installs production Composer dependencies, then pushes to WordPress.org SVN via 10up/action-wordpress-plugin-deploy@2.3.0

Required setup

Two repository secrets must be configured before the workflow can publish:

Secret	Value
WPORG_SVN_USERNAME	WordPress.org committer username
WPORG_SVN_PASSWORD	WordPress.org password / application password

The plugin must be submitted and approved at wordpress.org/plugins/developers/add/ before automated deploys will succeed.