fix(posts): add 'published' action for post status transitions

[faisalahammad]

Summary

Add a published action value to the Posts connector so users can alert on, filter by, and surface post-publish events specifically — instead of lumping them under the generic updated or created actions.

Fixes #1813

Changes

connectors/class-connector-posts.php

Before: get_action_labels() returned only updated, created, trashed, untrashed, deleted. The callback summary said “X published” but the logged action was updated or created.
After: Added published label and set action = 'published' whenever the new status is publish (draft→publish, new→publish, future→publish). The created fallback is now guarded so it does not override published for brand-new posts that go straight to publish.

tests/phpunit/connectors/test-class-connector-posts.php

Updated every new_status = 'publish' expectation in test_callback_transition_post_status to assert the new published action. All other transitions unchanged.

Testing

1. Run npm run test-one -- --filter Test_WP_Stream_Connector_Posts — expect OK.
2. Upload plugin-fix-1813.zip to a WP 6.9+/PHP 7.4+ site, activate.
3. Go to Stream → Alerts → Add New, select Trigger type Action, confirm Published appears in the Action dropdown.
4. Publish a post. Go to Stream → Records, filter by Action = Published. Confirm the record appears with summary like "Hello World" Post published.
5. Verify existing transitions still log as expected: draft→draft = Updated, private→trash = Trashed, trash→publish = Untrashed, publish→publish = Updated.

Changelog

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