#67 torso replication, part 1: the dead-reckoning clock fix + the bug REPRODUCED on the rig

THE CLOCK FIX (landed, verified live).  The replicant torso's extrapolation
window was hardwired to ZERO: both shim accessors returned the same field
(torso.hpp, the "dormant in single-player" note).  The engine maintains both
clocks exactly as the binary expects -- WriteUpdateRecord stamps
lastUpdate=lastPerformance on the master, ReadUpdateRecord stamps
lastUpdate=Now() on the replicant (SIMULATE.cpp:276/296, the 1995 "HACK"
comment intact) -- so the fix is one mapping: GetCreationTime (misnamed; now
GetLastUpdateTime) reads lastUpdate.  ComputeTargetTwist's
`current - lastUpdate` window is real again.  Why legs always replicated
while torsos did not: Mover is ENGINE code reading these fields natively; the
Torso is our reconstruction with the collapsed shim.  Rig-verified: the
copy-side log now shows distinct lastUpd/now values.

THE FIELD BUG REPRODUCED (2-pod rig, thor vs thor -- thor because the first
attempt used FOGDAY's Black Hawk, whose torso is authentically FIXED like the
Owens: hEn=0, limits +/-0.01 deg):

    [torso-copy] cur=-3.31613 target=-3.31613 atUpd=-3750

The replicant renders at EXACTLY its twist limit (thor: +/-3.31613 rad)
because twistAtUpdate holds garbage (-3750) and the limit clamp slams it to
the stop -- "twisted full right but was not using TT", on demand.  An earlier
run poisoned it with 2.1e-44 (= int 15 as float, suspiciously the torso's
subsystem index).

NARROWED: the tx/rx probes added here (BT_TORSO_LOG prints every torso record
both directions, header + raw payload dwords) logged ZERO records in the
poisoned runs -- Torso::Read/WriteUpdateRecord never executed.  The garbage
therefore arrives OUTSIDE the torso record path: a raw state write during
mech spawn/consolidation spraying the torso's fields (stream-walker framing
or a consolidation blit).  That writer is part 2's hunt; the probes and the
deterministic repro make it a short one.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

game/reconstructed/torso.cpp

@@ -341,7 +341,7 @@ Torso::Torso(
 	hitElevTop   = hitElevBottom  = 0;					// @0x258 / @0x25C
 	hitTwistLeft = hitTwistRight  = 0;					// @0x260 / @0x264
 	recenterActive = 0;									// @0x274
-	lastUpdateTime = GetCreationTime();					// @0x254 = this[5]
+	lastUpdateTime = GetLastUpdateTime();					// @0x254 = this[5]
 
 	// bring-up verification (env BT_TORSO_LOG): the gyro cross-links to
 	// (Torso*)+0x1D8 (== currentTwist) at a RAW offset (mech.cpp:740), so the
@@ -465,9 +465,9 @@ void
 	Torso::ReadUpdateRecord(UpdateRecord *message)
 {
 	lastUpdateTime = GetCurrentTime();				// @0x254
-	if ((Scalar)(lastUpdateTime - GetCreationTime()) / MsPerSecond < MinSlewMs)
+	if ((Scalar)(lastUpdateTime - GetLastUpdateTime()) / MsPerSecond < MinSlewMs)
 	{
-		lastUpdateTime += (lastUpdateTime - GetCreationTime());	// stretch tiny windows
+		lastUpdateTime += (lastUpdateTime - GetLastUpdateTime());	// stretch tiny windows
 	}
 
 	Subsystem::ReadUpdateRecord(message);			// FUN_0041bd34
@@ -475,6 +475,23 @@ void
 	twistAtUpdate = RecordField(message, 0x10);		// @0x21C
 	twistVelocity = RecordField(message, 0x14);		// @0x1E8
 	twistRate     = RecordField(message, 0x18);		// @0x238
+
+	// #67 stream forensics (BT_TORSO_LOG): the copy received atUpd=2.1e-44
+	// (= int 15 as float) on the rig -- a mis-framed record.  Print the raw
+	// header + payload dwords of every record this torso consumes.
+	if (getenv("BT_TORSO_LOG"))
+	{
+		const unsigned int *raw = (const unsigned int *)message;
+		DEBUG_STREAM << "[torso-rec-rx] len=" << message->recordLength
+			<< " subID=" << (int)message->subsystemID
+			<< " recID=" << (int)message->recordID
+			<< std::hex
+			<< " p10=0x" << raw[4] << " p14=0x" << raw[5]
+			<< " p18=0x" << raw[6] << std::dec
+			<< " -> atUpd=" << twistAtUpdate
+			<< " vel=" << twistVelocity << " rate=" << twistRate
+			<< "\n" << std::flush;
+	}
 }
 
 //
@@ -503,6 +520,17 @@ void
 	WriteRecordField(message, 0x14, twistVelocity);	// @0x1E8
 	WriteRecordField(message, 0x18, twistRate);		// @0x238
 	twistAtUpdate = currentTwist;					// @0x21C snapshot at send
+
+	// #67 stream forensics: what the MASTER actually serialized.
+	if (getenv("BT_TORSO_LOG"))
+	{
+		DEBUG_STREAM << "[torso-rec-tx] len=" << message->recordLength
+			<< " subID=" << (int)message->subsystemID
+			<< " recID=" << (int)message->recordID
+			<< " twist=" << currentTwist
+			<< " vel=" << twistVelocity << " rate=" << twistRate
+			<< "\n" << std::flush;
+	}
 }
 
 
@@ -730,7 +758,7 @@ void
 	}
 	else
 	{
-		Scalar age = (Scalar)(lastUpdateTime - GetCreationTime()) / MsPerSecond;
+		Scalar age = (Scalar)(lastUpdateTime - GetLastUpdateTime()) / MsPerSecond;
 		currentTwist = Lerp(currentTwist, targetTwist, time_slice / (age + time_slice));	// FUN_004081e0
 	}
 	targetTwist = Min(targetTwist, horizontalLimitLeft);	// @0x1E0
@@ -776,12 +804,12 @@ Logical
 
 	if (isDamagedCopy == 0 || lastUpdateTime <= GetCurrentTime())
 	{
-		base    = GetCurrentTime() - GetCreationTime();	// this[0x10] - this[0x14]
+		base    = GetCurrentTime() - GetLastUpdateTime();	// this[0x10] - this[0x14]
 		slewing = False;
 	}
 	else
 	{
-		base    = lastUpdateTime - GetCreationTime();	// @0x254 - this[0x14]
+		base    = lastUpdateTime - GetLastUpdateTime();	// @0x254 - this[0x14]
 		slewing = True;
 	}