ChildRecordData syncing across projections seems like it can end up in bad states

[igorT]

In general we rely on keeping one copy of canonical data in a baseRecordData, and then having projections modify and read from the baseRecordData. This in general works, but in cases of nested records and nested arrays, we also have childRecordDatas in both baseRecordData and the projection. While changing individual properties on those nested records will work, if you add or remove entire records from the array childRecordDatas might get out of sync between the base and projection records. I fixed one of the issues in #884 but it's likely there are more similar ones.

[hjdivad]

@igorT can we add tests to confirm whether this issue is fully resolved by #884 or if we have additional gaps?

[igorT]

This issue is to track adding more tests/investigating if there are more issues