Doc: reorganize bilingual READMEs and build guide with reference renders

benchmarks/2mass_galactic_center_blackhole.md

@@ -0,0 +1,27 @@
+Git hash: dd8cf29dac557c881e5df1db15a58fae15294967
+
+```
+❯ time ./build/Release/schwarzschild_sky \
+  --psf-relative-tail 1e-8 \
+  --psf-min-y 0 \
+  --max-cache-psf-flux 1e8 \
+  --all-sky-catalog assets/2mass/processed/all_sky \
+  --refine-max-level 4 \
+  --refine-jacobian-min 0.2 \
+  --width 3840 --height 2160 \
+  --look-ra-deg 262.5 --look-dec-deg -30 \
+  --fov-deg 45 \
+  --coarse-cell-pixels 16 \
+  --exposure 1e13 \
+  --psf-fwhm-pixels 2.7 --psf-moffat-beta 4.5 \
+  --catalog-load-workers 4 \
+  --observer-radius 100 \
+  --hdr-output \
+  --output output/imgs/2mass_galactic_center_schwarzschild_R100_4k_1e13_beta4.5_16_4-full.png
+PSF cache ready: 64x64 phases, radius 47 px, relative tail 1e-08, tail abs 1e-06, boundary 1e-07, build 0.693 s
+
+Catalog prefetch: 64440 requested, 64440 newly loaded (343363141 stars), 0 unavailable in 48.016 s; 4 loader workers
+Rendered 598308919 images from 343363141 catalog stars to output/imgs/2mass_galactic_center_schwarzschild_R100_4k_1e13_beta4.5_16_4-full.png (ok)
+PSF splats: cached 598308919, cached wing-clipped 1365, direct fallbacks 0, discarded below min-Y 0
+./build/Release/schwarzschild_sky --psf-relative-tail 1e-8 --psf-min-y 0  1e8  21346.08s user 132.97s system 1520% cpu 23:32.47 total
+```