P7: subsystem-tree alarm unification -- the whole PoweredSubsystem weapon/power subtree is byte-exact

The reconstruction modeled the binary's 0x54 AlarmIndicator (FUN_0041b9ec) with undersized
stand-ins (AlarmIndicator==ReconAlarm==4B; HeatAlarm==8B) across the entire subsystem tree, so
every field above an alarm sat at the wrong compiled offset.  Retype every such stand-in to
GaugeAlarm54(0x54) and de-phantom each class against its ctor, so the whole PoweredSubsystem
subtree becomes byte-exact.  An 8-agent read-only decomp-mapping workflow decoded every ctor
first; then hands-on implementation.  static_assert-locked chain (verified vs the raw ctors):

  HeatSink 0x1D0
   -> PoweredSubsystem 0x31C   retype electricalStateAlarm@0x264 + modeAlarm@0x2B8   @004b0f74
   -> MechWeapon      0x3F0   retype weaponAlarm@0x350; delete 5 phantom tail fields  @004b99a8
   -> Emitter         0x478   delete outputVoltage/beamLengthRatio/firingArmed aliases
                              + beamHit*/beamColor/beamHitData/energyRampTime phantoms;
                              retype beamOrientation EulerAngles->Quaternion(16B)       @004bb120
   -> PPC             0x478   (no own fields)                                           @004bb888
  PoweredSubsystem -> Sensor  0x328   (no alarm; 3 own fields)                          @004b1d18
  PoweredSubsystem -> Myomers 0x358   (no alarm)                                        @004b8fec

New systemic bug-class instances fixed (added to the CLAUDE.md checklist):
  * alias field    - Emitter outputVoltage==inherited rechargeLevel@0x320; beamLengthRatio==
                     beamScale.z@0x434; firingArmed==inherited useConfiguredPip@0x3E0
  * phantom field  - MechWeapon segmentReference/pipSegment/hasTarget/targetPoint/muzzlePoint
                     (past 0x3F0); Emitter beamHitPoint/beamImpact/beamImpactScalar/beamColor/
                     beamHitData/energyRampTime (binary writes inherited damageData/voltageScale
                     or the value is a method local)

Non-layout fixes required in the same wave:
  * outputVoltage->rechargeLevel also in the compiled GAUSS.CPP:74/93 (external readers of the
    removed Emitter field -- must grep EVERY TU, not just the class's own .cpp)
  * MechWeapon::GetMuzzlePoint reimplemented faithfully (removed muzzlePoint collided with
    Emitter's own fields at 0x3F0) via a BTResolveWeaponMuzzle void* bridge in mech4.cpp,
    resolving the weapon's mount segment (inherited this+0xdc) through the owner segment table
  * DetachFromVoltageSource fixed to set electricalStateAlarm not modeAlarm (raw @004b0e30
    writes the 0x264 alarm)

The vehicleSubSystems aux-screen gauge raw reads (btl4gau2.cpp:868/952 at subsystem+0x2b8/+0x278)
and the Sensor RadarPercent path now read the CORRECT byte offsets (garbage under the short layout).

Verified: combat DESTROYED-in-8, 28 shots, 0 crashes, heat heatEnergy=1.34e7, every static_assert
lock passes, heapcheck-clean through construction (the phase the isolated PoweredSubsystem retype
had overflowed).  LESSON: a factory-bridge runtime Check(sizeof<=alloc) does NOT fail the build --
only a static_assert sizeof lock catches alloc overflow at compile time.

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

game/reconstructed/mech4.cpp

@@ -655,6 +655,29 @@ Scalar
 	return 0.0f;
 }
 
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+// BTResolveWeaponMuzzle -- the faithful FUN_004b9948 (MechWeapon::GetMuzzlePoint)
+// muzzle resolve: look up the weapon's mount segment (index, from the subsystem's
+// inherited this+0xdc slot) in the owner Mech's segment table and transform it to
+// world.  Lives here (a complete-Mech TU with the segment API); mechweap.cpp treats
+// `owner` as a raw pointer so it calls this via a void* bridge instead of the Mech API.
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+void
+	BTResolveWeaponMuzzle(void *ownerMech, int segIndex, Point3D &out)
+{
+	Mech *m = (Mech *)ownerMech;
+	if (m == 0) { out = Point3D(0.0f, 0.0f, 0.0f); return; }
+	EntitySegment *seg = m->GetSegment(segIndex);		// owner+0x300 table, GetNth(index)
+	if (seg != 0)
+	{
+		AffineMatrix mw;
+		mw.Multiply(seg->GetSegmentToEntity(), m->localToWorld);	// segment -> world (== mech4 gun-port path)
+		out = mw;										// Point3D = matrix W_Axis translation
+	}
+	else
+		out = m->localOrigin.linearPosition;			// safe non-garbage fallback (owner origin)
+}
+
 void
 	Mech::PerformAndWatch(const Time& till, MemoryStream *update_stream)
 {