engine: expose world version through RefAPI

engine/client/cl_render.c

@@ -207,6 +207,8 @@ intptr_t CL_RenderGetParm( const int parm, const int arg, const qboolean checkRe
 			return pfnNumberOfEntities();
 		case PARM_NUMMODELS:
 			return cl.nummodels;
+		case PARM_WORLD_VERSION:
+			return world.version;
 		}
 	}
 	return 0;

engine/ref_api.h

@@ -261,6 +261,7 @@ typedef enum
 	PARM_LOCAL_GAME        = -11,
 	PARM_NUMENTITIES       = -12, // local game only
 	PARM_NUMMODELS         = -13, // cl.nummodels
+	PARM_WORLD_VERSION     = -14,
 } ref_parm_e;
 
 typedef struct ref_api_s