gauges: reconstruct cmCrit -- subsystem-critical tint; ColorMapper family complete [widget recon 5]

Reconstructs ColorMapperCritical -- tints a schematic colour by a subsystem's
operational state (the "critical" secondary display mode):
- CriticalConnection (@004c3598/@004c3610): src==0 -> 0; src->simulationState==1
  (DestroyedState) -> 100; else the subsystem's own damage-zone damageLevel*100.
- ColorMapperCritical::Make/ctor (@004c3ddc/@004c3e40): FindSubsystem by name +
  wire the CriticalConnection.

Resolved the subsystem damageZone@0xE0 shadow: MechSubsystem::damageZone is
declared ReconDamageZone*, but the assignment (mechsub.cpp: damageZone =
(ReconDamageZone*)new DamageZone(...)) shows the pointer IS a real engine
DamageZone -- so cast it back and read damageLevel. Added public accessors
GetSimulationState()/GetDamageZoneProxy() to MechSubsystem (those fields are
protected; mirrors how HeatConnection reads the public currentTemperature).

Completes the ColorMapper family (cmHeat, cmArmor, colorMapperMultiArmor,
cmCrit). Verified: parses, builds, all subsystems resolve (0 warnings), no
/FORCE unresolved, combat un-regressed (TARGET DESTROYED, 0 crashes), stable.

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

game/reconstructed/btl4grnd.cpp

@@ -133,6 +133,7 @@ MethodDescription
 			&HeadingPointer::methodDescription,		// "headingPointer" -- compass needle + heading
 			&ColorMapperArmor::methodDescription,	// "cmArmor" -- per-zone armor-damage tint
 			&ColorMapperMultiArmor::methodDescription,	// "colorMapperMultiArmor" -- worst-of-8-zones tint
+			&ColorMapperCritical::methodDescription,	// "cmCrit" -- subsystem-critical-state tint
 			&BTL4ChainToPrevious
 		};