Add Create Strategies

[chrisvanrun]

Part of the large PR:

• Major refactor of helper functions #167

This PR adds creation strategies for creating interdependent objects that can be used for creating display sets and archive items. Strategies should return an item that can be used to finalize the strategy, the CIV strategies return a ComponentInterfaceValuePostRequest.

Only tests for the prep stage of the strategies have been added since testing the actual execution of the strategies is non-trivial and is heavily reliant on the involved integration tests. The strategies are a result of heavy testing and extraction from the helper functions on the original PR.

This PR implements the logic behind the following:

Allowing both str, and list[str]

Sourcing a CIV from one file no longer requires a one-lengthed list, the helper functions automagically handle both. This also applies to pathlib.Path.

RE-use of images / CIVs

Can provide a CIV or Image to the strategies and it will be re-used.

[jmsmkn]

I'm aware of this but because it is non-pitch related and still large it has low priority for me, so keeps getting pushed back by higher priority things. It may still be a while.

[chrisvanrun]

I'm aware of this but because it is non-pitch related and still large it has low priority for me, so keeps getting pushed back by higher priority things. It may still be a while.

Check, I thought as much! Given its size and low priority it makes perfect sense. The assignment was a subtle async poke ;-)