This keys off of the pass name to decide if channel should be 32 bit.It works similarly to the way Mist and Depth are handled.
It'll allow for one multilayer exr sequence output with a working cryptomatte while also using less space for channels that don't need full float
If keying off the channel name isn't ideal, maybe `rp` could have some sort of `type` attribute that could be used to decide what gets full float.
The current limitations of this are in the compositor. I have been unable to find a channel name in `OutputOpenExrMultiLayerOperation` to use.
I don't think this needs any user interface. The documentation on Cryptomatte should warn that those passes from a render are always full float