Spike: Leveraging the existing create item/holding forms from orders/receiving

Overview:
As part of the check-in flow we need the ability to create a piece (e.g. we have an order for a magazine and the March issue just arrived). Part of creating the piece may involve creation of an accompanying holding and item record. Instead of duplicating and maintaining separate create holding/item forms, it would be ideal if we could create UI plugins which load those forms, and handling the saving of the record (to inventory via API).

After discussing with (mpk35 and mattj), it sounds like this is uncharted territory. Most (all?) existing plugins are for lookups, not record creation.

Purpose:
Investigate the best approach to this, identify any major pitfalls/blockers, and ideally create a POC which could later be formalize into two separate plugins (e.g. ui-inventory-create-holding-plugin & ui-inventory-create-item-plugin)

Acceptance Criteria:

• Findings are documented on the wiki
• POC code exists and is either checked-in or attached to the wiki page mentioned above and/or to this story

Time Box: 2 days

NOTE: The ability to lookup/select an existing holding is also required, but I think that is probably more in-line with plugins that already exist. I mention it here in case it would make sense to roll this into the plugin for holding creation... e.g. a find or create holding plugin. I'm assuming that it would be preferable to have separate lookup/create plugins, but figured it couldn't hurt to mention here anyway.