The ten network layer dispatches only need dispatch serialization, not a
global memoryBarrier flush: each layer's cross-block traffic goes through
its own buffers, already published by the preceding stage's flush. An
empty compute->compute pipeline barrier keeps the ordering and removes
the flush cost: whole-frame median 2515.0 -> 2431.7 us at Balanced
(1488x837 -> 2560x1440), 3818.9 -> 3773.3 at Quality, 1892.6 -> 1810.6
at Performance, byte-identical to the captured launches (chain test
10/10 layers 100.0%, frame test inf dB, 8- and 16-frame outputs match).
Also documents this session's discarded probes (intra-frame barrier
relaxation, colSum subgroup shuffle, downsample BLOCK_Y 32, expansion
EO stride 24, cross-frame pipelining analysis, the NO_ROUND 7.0%
rounding-free ceiling) and adds the round_half.glsl include guard.
woutermans
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