APIv4 - Enable getFields to find fields across implicit FK joins

[colemanw]

Overview

Now it is possible to retrieve field metadata for a joined entity via APIv4. E.g. from the Participant GetFields api, specifying the fieldName "event_id.title" will automatically retrieve field metadata from the Event API.

Before

Only entities own fields could be returned.

After

Possible to return fields from other entities.

Comments

This is the first step toward supporting implicit join fields in Search Kit.

[civibot]

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[eileenmcnaughton]

Before

After - I can't quite capture it - but the box knows it is looking for an integer (I was expecting it to present an option list but I think the metadata on parent_event_id is actually not quite right)

Does what it says on the box