environment: Bufferize the single audio frames

This improves the performances significantly in cores sending single
audio samples rather than batches, as sending them in batches avoids
emitting many costly signals stupidly often.

Fixes #20
4 jobs from wip/aplazas/audio-samples in 5 minutes and 5 seconds
Status Job ID Name Coverage
  Build
passed #212614
flatpak:demo

00:01:26

 
  Test
passed #212615
flatpak:tests

00:02:23

 
  Review
passed #212616
review

00:00:32

passed #212617
allowed to fail manual
stop_review

00:00:43