APIv4 - Add export action for managed entities

[colemanw]

Overview

New APIv4 action generates an exportable array suitable for use in a .mgd.php file.

Comments

.mgd.php files are tricky to hand-write; so this action is a nice time-saver and human-error-saver. But the really useful part of this api action is that it collects all references into a single array of managed entities. For example, exporting a SavedSearch will automatically include the search displays:

[civibot]

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[agileware-justin]

👍 up for the ability to export configuration.

[kurund]

Export functionality is working as expected. Here is what I did:

• Created a new 'Saved Search' using Search kit and then exported it.
• Created new extension on a separate CiviCRM instance and added exported saved search to SavedSearch.mgd.php
• After installing the extension saved search was correctly created and listed under packaged searches.

Good to merge.

[colemanw]

Thanks @agileware-justin and @kurund. Merging based on review.