Initial commit: bt411 -- standalone Windows BattleTech (Tesla 4.10 port)

Clean, self-contained extraction of the BattleTech-specific work from the
reverse-engineering workspace -- engine + game + content + build, with nothing
from Red Planet or the raw archive dumps. Builds green (Win32) and runs the
single-player drive->animate->target->fire->damage->destroy loop out of the box.

Layout:
  engine/   MUNGA + MUNGA_L4 shared 2007 engine, carrying our BT render/loader
            work (bgfload/L4D3D/L4VIDEO: BSL bit-slice decode, LOD/ground/shadow
            models) + image codec; the minimal rp/ headers the audio HAL needs
  game/     reconstructed BT logic + surviving-original BT source + fwd shims
            + WinMain launcher
  content/  full runtime tree (BTL4.RES, VIDEO/, GAUGE/, AUDIO/, eggs, BTDPL.INI)
  docs/     format specs + reconstruction ledgers
  reference/ raw Ghidra pseudocode (recon source-of-truth) + decomp exporter
  tools/    MP console emulator + map/resource scanners

One top-level CMake builds munga_engine lib + bt410_l4 game lib + btl4.exe.
All paths relativized (186 fwd shims + ~437 CMake abs paths -> repo-relative);
DXSDK is the one external, overridable via -DDXSDK. Verified: builds to a
byte-identical 2.27MB exe and runs combat (TARGET DESTROYED, 0 crashes) against
the bundled content.

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

engine/MUNGA/TIME.cpp

@@ -0,0 +1,117 @@
+#include "munga.h"
+#pragma hdrstop
+
+#include "time.h"
+
+//#############################################################################
+//###########################    System Clock    ##############################
+//#############################################################################
+
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+void SystemClock::TogglePause()
+{
+	//
+	//--------------------------------------------------------------------
+	// If the clock is currently paused, figure out how long it was paused
+	// and add that to the pause delay
+	//--------------------------------------------------------------------
+	//
+	if (timer.pauseStart)
+	{
+		timer.pauseTime += GetRTC() - timer.pauseStart;
+		timer.pauseStart = 0;
+	}
+	else
+	{
+		//--------------------------------------------------------
+		// Otherwise, start pausing by marking what time it is now
+		//--------------------------------------------------------
+		timer.pauseStart = GetRTC();
+	}
+}
+
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+volatile Time& Now()
+{
+	static Time result;
+
+	//
+	//-------------------------------------------------
+	// If we are in pause mode, return the paused clock
+	//-------------------------------------------------
+	//
+	if (SystemClock::timer.pauseStart)
+	{
+		result = SystemClock::timer.pauseStart;
+	}
+	else
+	{
+		//----------------------------------------------------------------
+		// Otherwise, return the timer minus the amount of pause time lost
+		//----------------------------------------------------------------
+		result = SystemClock::GetRTC() - SystemClock::timer.pauseTime;
+	}
+
+	return result;
+}
+
+
+double HiResNow()
+{
+   return SystemClock::GetHiRes();
+}
+
+__int64 HiResNowTicks()
+{
+	return SystemClock::GetHiResTicks();
+}
+
+__int64 HiResCounterFreq()
+{
+	return SystemClock::perfCounterFreq;
+}
+//#############################################################################
+//###############################    Time    ##################################
+//#############################################################################
+
+Time Time::Null(SystemClock::timer);
+
+#if defined(USE_SIGNATURE)
+	int Is_Signature_Bad(const volatile Time *)
+	{
+		return false;
+	}
+#endif
+
+//
+//#############################################################################
+//#############################################################################
+//
+Logical Time::TestInstance() const volatile
+{
+	return true;
+}
+
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Time functions ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+//
+//#############################################################################
+//#############################################################################
+//
+void Convert_From_Ascii(const char *str, Time *time)
+{
+	Check_Pointer(str);
+	Check_Signature(time);
+
+	Scalar seconds;
+
+	seconds = atof(str);
+	*time = seconds;
+	Check(time);
+}
+
+#if defined(TEST_CLASS)
+	#include "time.tcp"
+#endif