warp_update() model, 100000 updates, STARS=225
min index written    = 1
max index written    = 64000  (framebuffer = 64000 bytes)
writes at vid[64000] = 706  (byte past framebuffer)
writes >= 64000      = 706
VERDICT: OFF-BY-ONE CONFIRMED -- star rests at exactly SCRW*SCRH and is drawn+erased at vid[64000]; no index beyond 64000 ever occurs (`>` at warp_saver.c:74 should be `>=`)