Audio Phase 4d (AUDIO_FIDELITY F5): footStep is the authored CONTACT LEVEL

The binary's per-frame perf (disasm @0x4a9e80-0x4a9eb6 leg / @0x4aba86-
0x4abab9 body) computes footStep@0x394 = (jointlocal.y <= *footStepThreshold)
with the threshold pointer = SequenceController+0x20 = &ANI hdr[2] -- the
header word the engine's own AnimationInstance captures (JMOVER.cpp:1415)
and our SelectSequence skipped.  States 0/1 retain the value.

Port: SelectSequence captures hdr[2]; PerformAndWatch evaluates the contact
level per frame from the cached jointlocal root joint (leg channel drives
the pose); the 150 ms clip-transition pulse + decay are RETIRED (steps fired
at clip boundaries with a fixed width; clips whose root crosses twice or
never counted wrong).

Live verification (30s walk): the authored threshold decodes real
(-0.232 root height); rootY oscillates across it per stride (-0.26 contact /
-0.19 swing) with clean 0->1->0 transitions per leg state (5/6/7); 34
footfall deliveries at stride rate with per-stride varying gains.

Also closes F23(2): the 17 authored AnimationState trigger states fire
empirically -- the EngineShiftFwd/Rev heard during the gait dead-band hunt
WERE states 10/11/14/15; the runtime clip numbering is correct.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

game/reconstructed/seqctl.cpp

@@ -149,6 +149,10 @@ void
 	int *hdr = (int *)desc->resourceAddress;	// resource data (binary: *(desc+0x3c))
 	keyframeCount = hdr[0];						// @0x14 frameCount
 	jointCount    = hdr[1];						// @0x18 jointCount
+	// (AUDIO_FIDELITY F5) hdr[2] = the clip's authored footstep contact
+	// threshold (root height); previously skipped.  Same capture as the
+	// engine's AnimationInstance (JMOVER.cpp:1415).
+	footStepThreshold = (Scalar *)(hdr + 2);	// @0x20
 
 	int *p = hdr + 3;							// jointIndices follow hdr[0..2]
 	jointIndices  = p;							// @0x1c (jointCount ints)