Auto merge of #8478 - KiChjang:constellation-two-receivers, r=Ms2ger
Auto merge of #8478 - KiChjang:constellation-two-receivers, r=Ms2ger

Split chan and receiver_port into script and compositor flavors

Partial #8356. Currently this doesn't build because of a lint denying me to user unsafe code, which unfortunately the select! macro falls under. Not sure what to do there.

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