Torso: the TWIST goes LIVE -- electrical watchdog chain, centered crosshair, coherent controls (task #57/#58)

The MadCat torso twists, the view turns with it, and targeting follows.
Three reconstruction fronts closed:

THE ELECTRICAL WATCHDOG CHAIN (why the torso never powered up):
- PowerWatcher::UpdateWatch reconstructed (@004b181c, the REAL registered
  Performance -- PTR @0050f5fc; Ghidra missed the fn start): the watchdog
  MIRRORS the watched subsystem's electrical level (+0x278), brownout
  downgrade when gen output <= minVoltage% x rated.  @004b1804 relabeled
  ResetToInitialState (slot 10) -- the old "Simulation" tag was wrong.
- The factory watcher-CONNECT pass reconstructed (vtable slot +0x38,
  @004aee2c/@004b1a40 byte-identical, recovered from raw exe bytes):
  watchedLink.Add(roster[watchedSubsystem]) on the master node.  Was the
  SubProxy::Start() no-op -- every watchdog sat at 0 forever.
- MinVoltageScale = 0.01 (a 10-byte x87 literal @0x4b1924; was 1.0f =
  permanent brownout) and PowerWatcher's Derivation chains its REAL base
  HeatWatcher (the HeatableSubsystem stand-in broke IsDerivedFrom for the
  whole Torso/Searchlight/ThermalSight family).
- KB correction swept: derivation tag 0x50e604 = HEATWATCHER (not
  "HeatSink"); the btl4gaug heat-widget gate now tests it via the
  BTIsHeatWatcher bridge.

THE CROSSHAIR (task #58 forensics, 6-agent workflow + live probes):
- The VIEW is TORSO-MOUNTED: jointtorso -> jointeye -> siteeyepoint in
  every twist-capable .SKL; the camera + canopy ride the same hinge
  subtree through HingeRenderable's live matrix-stack compose -- ALREADY
  WORKING in the port.  The crosshair stays screen-centered (center IS
  the boresight); the twist reads on the tape carets/compass/radar.
- The real bug was the port's gBTAimX = tan(twist) slew (the falsified
  "body-mounted view" model): the camera already carried the twist, so
  the crosshair counter-slid to hull-forward and the fire ray with it.
  Deleted; the pick ray inherits the twist from the yawing eye basis.
- Two instrumentation traps documented (chase-eye-as-default-camera,
  BT_FORCE_TORSO clobbering real joints -> the hook now only fills
  unresolved ones); an over-correcting explicit eye compose was added on
  those false readings and retired the same day.

CONTROLS + REPLICATION:
- Q/E spring-center on release (the axis is a twist-RATE demand; the old
  hold-deflection model drifted forever); X also zeroes the axis and
  pulses the authentic torso Recenter (@004b6918).  M cycles control
  mode via the real CycleControlMode body.
- Torso update-record DIRECTION fixed: engine truth is Write=serialize /
  Read=apply; @004b6a78 is the READ (was mislabeled Write) and the
  missing WRITE @004b6a1c recovered from raw disasm (recordLength 0x1C,
  twist/vel/rate at +0x10/14/18) -- kills the replicant's 0xCDCDCDCD
  -140-degree ghost twist.
- Marching-ghost desync: 4 Standing-case guards zero stale reverse
  cycleSpeed (negative cadence passed the <= ZeroSpeed stop gate).
- Kill credit rerouted to the OBSERVED killer (lastInflictingID ->
  killer's player link) -- kills count, target K/D populates.

KB: subsystems.md (watcher chain), multiplayer.md (record direction),
combat-damage.md + gauges-hud.md + cockpit-view.md (torso-mounted view
re-correction), decomp-reference.md (new addresses + tag fix),
open-questions.md (dead capability-roster loops 2-4, snapshot CD read).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

game/reconstructed/mechdmg.cpp

@@ -1092,8 +1092,21 @@ void
 		}
 		if (d != 0)
 		{
-			BTSpawnDamageEffect(owner, d->effectResource,	// explosion AT the zone's
-					zone->segmentIndex);					// segment (world position)
+			// THE AUTHENTIC CHAIN (@004d097c dispatcher, landed 2026-07-13):
+			// RendererManager::StartEntityEffect -> the Renderer message
+			// handler [T0: GameModel resolve + ExplosionResourceTable
+			// graphic-state remap] -> BTL4VideoRenderer::
+			// StartEntityEffectImplementation -> the effect ATTACHED to the
+			// zone's segment (smoke follows the walking mech) -- and the
+			// AudioRenderer's implementation hears the same message (zone
+			// sounds ride free).  Explosion::Make fallback only when the
+			// manager isn't up (early bring-up).
+			extern int BTStartZoneEffect(Mech *mech, void *zone, int resource);
+			if (!BTStartZoneEffect(owner, zone, d->effectResource))
+			{
+				BTSpawnDamageEffect(owner, d->effectResource,	// explosion AT the zone's
+						zone->segmentIndex);					// segment (world position)
+			}
 			zone->ApplyDamageGraphicState(d->graphicState);	// destroyed skin (graphic state)
 			// A graphic-state change means the segment's MODEL changed (intact ->
 			// destroyed variant, keyed by GetVideoObjectName(skl, gstate)).  Fire