[CODAP] Unchecking and then rechecking variable doesn't restore data in copy/saved version

[Nancy-Salpepi]

Test device
MacBook Air M1 chip

Operating System
15.0.1

Browser
Safari 18.0.1

Problem description
For phetsims/qa#1157, if I uncheck and then check any previously checked variables in a saved or copy version, when the column reappears it is blank.

Steps to reproduce

1. Check all the setup variables
2. Collect some data on any screen
3. Save or Make a Copy
4. In the saved version/copy uncheck one of the variables -- column disappears in the table
5. Recheck that variable -- column reappears but the data is lost

Visuals

blank.column.mp4

[samreid]

Save or Make a Copy

I believe @matthew-blackman and I observed that in "Save" or "Make a Copy", CODAP manages the data in the table and we do not have control over repopulating it correctly. (It is more like a "deep copy" than a live dynamical wired-up view). This solved some problems but created other problems.

[samreid]

@matthew-blackman indicated there is a chance that the "hidden" strategy in #357 may solve this. But that depends on the "hidden" values coming along with the copy. If they do, it will work properly. If they don't, we will have to investigate writing our own workaround for that. Or an updated way of dealing with the sparse data model.