* Adding response/request models
* Adding mapping
* Adding factory
* Adding controllers
* Moved to correct (generic domain) namespace
* Renamed to reflect the correct domain + renamed IsAllowed to IsCompatible
* Renaming + TODO
* Removed presentation logic + TODO
* Fixed controller
* Attempt for generic implementation
* Enable composition of media types + refactor content/media type editing tests to prove it (and a little renaming of a mis-named property)
* Remove unused classes
* Introducing GetAvailableCompositionsAsync to EditingServices
* Implement GetAvailableCompositionsAsync
* Base share implementation
* Tests
* Tests
* Renaming
* Clean up controller
* Clean up test
* Remove redundant check
* Create and use generic models
* Add shared implementation
* Fix and rename doc type mapper
* Fix document Type factory
* Add missing response type
* Create a base request model
* Make key nullable when new item
* Media type response models
* Default isElement to false and remove isElement param from media type related things
* Create mappings for media type compositions
* Inject generic base service to reuse implementation amongst concrete services
* Add new composition endpoints for media type
* Use specific type
* Add a reference comment to other test suite
* Add more test cases
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Co-authored-by: kjac <kja@umbraco.dk>