gauge wave P2d: GeneratorCluster un-gated -- the 4 generator panels render

Root-caused the P2c abort with a cdb attach to the frozen abort dialog: the stack
was Gauge::Execute (GAUGE.cpp:598) -> abort, via GuardedExecute <- Update <-
ProcessOneActiveGauge.  The engine base Gauge::Execute is Fail("not overridden")
-> abort, so an ACTIVE container that doesn't override Execute aborts by design;
GuardedExecute's SEH can't catch an abort().  The decode's "GeneratorCluster
overrides ONLY the dtor / renders via its children" was wrong -- the 1995 base
Gauge::Execute was a no-op, the 2007 WinTesla engine's aborts, so the container
MUST override Execute (the sibling SubsystemCluster does).

FIX: give GeneratorCluster the two container overrides (mirroring SubsystemCluster):
- BecameActive() -- blit the panel's static background pixmap (DrawPixelMap8) and,
  by overriding the default, DON'T self-inactivate so the panel stays active.
- Execute() -- no-op (the 5 self-registered child gauges draw the dynamic content;
  the override exists only to avoid the base Fail->abort).

Re-registered in BTL4MethodDescription[].  Verified DBASE+dev gauges: all 4
generator panels (A/B/C/D) render -- blue OutputVoltage bars (the @004c72ac
ScalarBarGauge Scalar* variant), labels, status lamps -- 0 "BecameActive not
defined" warnings, NO abort, combat un-regressed (TARGET DESTROYED).  Phase 2 is
now COMPLETE (4/4 widgets: LeakGauge, VertNormalSlider, PilotList, GeneratorCluster).

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

game/reconstructed/btl4gau2.cpp

@@ -785,6 +785,36 @@ GeneratorCluster::~GeneratorCluster()
 	backgroundImage = NULL;
 }
 
+//
+// BecameActive -- paint the panel's static background pixmap.  MUST override the
+// default (which self-inactivates the panel + warns); a no-op keeps the panel
+// active so its 5 child gauges (self-registered) keep drawing.  The bg is drawn
+// here (on activation) beneath the children.
+//
+void
+	GeneratorCluster::BecameActive()
+{
+	L4Warehouse *warehouse = (L4Warehouse *)renderer->warehousePointer;
+	PixelMap8 *bg = warehouse->pixelMap8Bin.Get(backgroundImage);	// already AddRef'd by the ctor
+	if (bg != NULL)
+	{
+		localView.MoveToAbsolute(0, 0);							// vtbl+0x24
+		localView.DrawPixelMap8(True, 0, bg, 0, 0,				// vtbl+0x5C (opaque, full image)
+			bg->Data.Size.x - 1, bg->Data.Size.y - 1);
+	}
+	warehouse->pixelMap8Bin.Release(backgroundImage);			// balance this Get
+}
+
+//
+// Execute -- the panel itself has no per-frame content (the temp/voltage/leak/lamp
+// children each Execute independently), but Execute MUST be overridden: the engine
+// base Gauge::Execute is Fail(...)->abort (GAUGE.cpp:598).  No-op.
+//
+void
+	GeneratorCluster::Execute()
+{
+}
+
 
 //###########################################################################
 //###########################################################################

game/reconstructed/btl4gau2.hpp

@@ -267,6 +267,14 @@
 			int lamp_on_color, int lamp_off_color,
 			const char *identification_string);
 		~GeneratorCluster();					// @004c7778
+		// A container panel MUST override BecameActive + Execute: the engine base
+		// Gauge::Execute is Fail("not overridden")->abort (GAUGE.cpp:598), and the
+		// default BecameActive self-inactivates.  The panel draws its static
+		// background pixmap; the 5 self-registered child gauges draw the dynamic
+		// content.  (The decode's "only the dtor is overridden" was wrong: the
+		// 1995 base Gauge::Execute was a no-op, the 2007 engine's aborts.)
+		void	BecameActive();
+		void	Execute();
 	protected:
 		char	*backgroundImage;				// @0x90  this[0x24]  interned .pcc (pixelMap8Bin AddRef'd)
 		int		secondaryColor;					// @0x94  this[0x25]  = leak colorB (stored, unread here)

game/reconstructed/btl4grnd.cpp

@@ -146,18 +146,7 @@ MethodDescription
 			&BitMapInverseWipe::methodDescription,		// "LeakGauge" -- coolant-leak inverse-wipe (Condenser/CoolantMassLeakRate)
 			&VertNormalSlider::methodDescription,		// "vertNormalSlider" -- condenser valve-setting slider (heat MFD)
 			&PilotList::methodDescription,				// "pilotList" -- Comm KILLS/DEATHS pilot roster
-			// GeneratorCluster is reconstructed (btl4gau2.cpp) + its infra is in place
-			// (Generator OutputVoltage table + the @004c72ac ScalarBarGauge variant), but
-			// registering it aborts at runtime: the 4 panels build (the 4 "BecameActive not
-			// defined" warnings fire) then abort() -- isolated to the PARENT lifecycle (the
-			// abort persists with all 5 children nulled; no pure virtuals; the ctor path is
-			// unguarded by the SEH GuardedExecute).  The sibling SubsystemCluster overrides
-			// BecameActive/Execute/TestInstance whereas the decode has GeneratorCluster
-			// overriding ONLY the dtor -- that "inherits only dtor" claim is the prime
-			// suspect.  DEFERRED: unregistered so it parse-skips (never built) -> no abort;
-			// the other 3 P2 widgets ship clean.  Re-enable this line once the parent
-			// lifecycle is resolved.
-			// &GeneratorCluster::methodDescription,	// "GeneratorCluster" -- 4 generator panels (buttons 9-12)
+			&GeneratorCluster::methodDescription,		// "GeneratorCluster" -- the 4 generator engineering panels (buttons 9-12)
 			&BTL4ChainToPrevious
 		};