Stereo Display

Implement stereo image display 

MVP would be two filepaths for left and right eye and interlaced (or side by side)
Possibly relies upon Open image IO reader, need to investigate

Beyond mvp:

1. Add support for media type with left and right streams (could be generalised to allow media object with multiple streams, stereo being a specialisation of that)

2. Recognise media as stereo on import> stereo exrs can be inferred from header
> arbitrary files - need API command to add arbitrary streams to a media object. Pipeline hook to customise finding left and right streams to be passed in

3. Virtual streams to group left/right into nicely named accessible source
4. Display options:
> Half side by side
> Interlaced

The issue names no files, tests, or entry points; start by investigating the existing media/display architecture and whether the Open Image IO reader can provide the required image streams. Define the MVP boundary around left/right filepaths and interlaced or side-by-side display, with completion verified against those listed behaviors.

Written by the indexing model from the issue text.