Replace a ton of trivial #ifdefs with runtime checks

This one is big, but unless I missed something, should be all be
trivial.

scripted-diff with the following, then manually tweaked whatever needed:
```

if [ $# -ne 3 ]; then
    echo "Usage: $0 '<pattern>' '<replacement>' '<filename>'"
    exit 1
fi

pattern="$1"
replacement="$2"
filename="$3"

if [ ! -f "$filename" ]; then
    echo "Error: File $filename does not exist."
    exit 1
fi

sed -i '/'"$pattern"'/ {
    :loop
    $ !{
        N
        /'"$pattern"'.*\n.*#endif/ {
            s/'"$pattern"'/'"$replacement"'/
            s/#else/} else {/
            s/#endif/}/
            P
            D
        }
        /'"$pattern"'/ b loop
    }
}' "$filename"

echo "Replacement complete in $filename"
```

h/t to Grok2 for the sed command

Ja2/JA2 Splash.cpp

@@ -5,6 +5,7 @@
 #include "Timer Control.h"
 #include "Multi Language Graphic Utils.h"
 #include <stdio.h>
+#include <language.hpp>
 
 UINT32 guiSplashFrameFade = 10;
 UINT32 guiSplashStartTime = 0;
@@ -13,10 +14,10 @@ extern HVSURFACE ghFrameBuffer;
 //Simply create videosurface, load image, and draw it to the screen.
 void InitJA2SplashScreen()
 {
-#ifdef ENGLISH
+if( g_lang == i18n::Lang::en ) {
 	ClearMainMenu();
 
-#else
+} else {
 	UINT32 uiLogoID = 0;
 	HVSURFACE hVSurface; // unused jonathanl	// lalien reenabled for international versions
 	VSURFACE_DESC VSurfaceDesc; //unused jonathanl // lalien reenabled for international versions
@@ -69,7 +70,7 @@ void InitJA2SplashScreen()
 	GetVideoSurface( &hVSurface, uiLogoID );
 	BltVideoSurfaceToVideoSurface( ghFrameBuffer, hVSurface, 0, iScreenWidthOffset, iScreenHeightOffset, 0, NULL );
 	DeleteVideoSurfaceFromIndex( uiLogoID );
-#endif // ENGLISH
+} // ENGLISH
 
 	InvalidateScreen();
 	RefreshScreen( NULL );