The only functionally relevant change is that orbiter scenes are now saved via SkinFlavourItem (as of U39?).
The rest is cleanup of the types because the ship customization stuff was duplicated all over the place.
This seems to be needed for the client when refreshing the ship after loading into a mission as it does not resync the ship otherwise.
Closes#1629
Reviewed-on: #1632
Co-authored-by: Sainan <63328889+Sainan@users.noreply.github.com>
Co-committed-by: Sainan <63328889+Sainan@users.noreply.github.com>
