* Prevent collection nesting on import into a my items collection
My Items collections do not support nested collections. The import source hierarchy needs to be flattened into the My Items collection
* Introduce new types for folder and collection relationship
Makes it easier to identify which position is for the cipherIndex and which is for the folder-/collection-index
* Fix assignment of ciphers to My items collection
* Remove unneeded type cast or assertions
* Add clarifying comment
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Co-authored-by: Daniel James Smith <djsmith85@users.noreply.github.com>
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