CLAUDE: item-4 R2 native - pixel-LoG + gated subtract-avg kernels on the resident render frame + camera-upload fast path

render_pix_log: NaN-aware LINEAR LoG (convolve2DLReLU form, fmaf throughout
so a same-order CPU std::fma replay is bit-exact) fused with the ruling-3.1
POST-LoG subtract-average (diff = LoG - avg resident detection frame, gated
EMA refresh, NaN-avg bootstrap seed) on the 640x512 sensor window of r_rbg.
render_avg_accum: NaN-aware raw-domain sum/cnt -> the next run's prior-
average file. Entries tp_proc_render_log_setup (ALL allocs at arm - the
no-alloc-class-in-loop rule; re-arm resets = rerun==fresh) and
tp_proc_render_log_get; render_scene enqueues both after render_dp on the
render stream, before render_done. KERNELS 45.

Enqueue shave: tp_proc_render_cameras fast path - scene meta+ERS only
(NULL radial/rbr = keep resident static tables), pinned double-buffered
staging + async copies on the render stream; no stream-sync, no per-scene
rByRDist H2D.

New case log_pipe (registered): L0 log-armed render bit-identical; L1 GPU ==
CPU float replay BIT-exact (raw/diff/avg/accum, 4 frames) + double oracle
rel 1.8e-7 of input mag; NaN substitution exercised; L2 prior base + median
gate, both populations non-empty; L3 rerun==fresh bit-identical; L4 camera
fast-path == full upload bit-exact. render_pipe --bench grows --log (R2
armed): render-8 re-verified 4.365 ms/scene in 8+8 carve, +0.15 with R2.
Full suite ALL PASS; compute-sanitizer 12.8 memcheck 0 errors.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>