Integrate addition of ckey to overlay a record in ILS with "Export to Catalog" button

[NancyL]

Describe the feature you'd like
Currently, to send a new record to Symphony, we need only to click on the "Export to Catalog" button; the record is sent and a local admin metadata description is created. To send a record to overlay another record in Symphony, we need to create the local admin metadata manually, adding the ckey in the description before we export to catalog. This is extra work for something which will be the more common workflow. It would be good if on clicking the "Export to Catalog" button, a dialog popped up that said something like "Add control number for overlaying; leave blank for new" with a box in which to enter the ckey. Then on clicking "okay" or whatever, the system would create a local admin metadata record with the ckey & source filled out.

Give an example
something like this:

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
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