Handoff

[Arclite]

Originally created on 2021-06-12T07:19:08.550Z at https://git.pado.name/highlighter/app/-/issues/182

[Arclite]

• On iOS, cache images when starting from bare image
• On iOS and macOS, handle missing image bookmark data
• On iOS, handle cloud asset identifiers
• On iOS and macOS, handle continuation streams to share image data