Replace routine for sd with yields, rejig cull thresholds

[m-m-adams]

This makes the time between audio rendering much more predictable, which means that the thresholds don't have to incorporate enough buffer to handle a large jump in rendering requirements

Because the time between renders is predictable it also means we can estimate based on the render time instead of the time between render calls, which is much more accurate

[github-actions[bot]]

Test Results

45 tests  ±0   45 :white_check_mark: ±0   0s :stopwatch: ±0s  8 suites ±0    0 :zzz: ±0   8 files   ±0    0 :x: ±0 

Results for commit b387738f. ± Comparison against base commit c9f3ee04.

:recycle: This comment has been updated with latest results.