v0.4.0 D375: crouch now emits C-down (the engine's real crouch input), not B

bondview2.c reads crouchDown = insightaimmode && (buttons & (D_JPAD|D_CBUTTONS))
(5318/5579): crouch is C-down WHILE IN AIM MODE, never the B button. M3's
IA_CROUCH -> GE_CONT_B (and the CrouchMode=1 latch) was inert, so crouch
never fired in the GEPD layout. Hold + latch now emit GE_CONT_D (0x0004).
N64-faithful side effect: S (IA_BACK, also C-down) crouches while aiming.
User re-test: aim (RMB/Left Shift) + Left Ctrl; hold or F10 Toggle.

docs/dev/findings-index.csv

@@ -251,3 +251,4 @@ D371,FIXED,"GEPD key-layout preset + reload/crouch bindings, v0.4.0 modern optio
 D372,FIXED,"Low-end perf preset (v0.4.0 modern options wave M5, 2026-09-27).",FIXED (headless-verified; awaiting user live accept):
 D373,FIXED,"In-game crosshair on/off + colour (v0.4.0 modern options wave M2, 2026-09-27).",FIXED (user live-tested; rule-2 sign-off recorded 2026-09-27):
 D374,FIXED,"GEPD becomes the default key layout; preset layering fix (v0.4.0 M3 playtest feedback, 2026-09-27).",FIXED (headless + user live-tested):
+D375,FIXED,Crouch wired to the wrong pad bit:,"FIXED (in tree, build clean; user re-test owed):"