Added NIL alternative for Builder generation, as nil value are optimi…

…zed away on declaration

scripts/CpObject.lua

@@ -74,15 +74,21 @@ function CpObject(base, init)
 end
 
 ---@class CpObjectUtil
-CpObjectUtil = {}
+CpObjectUtil = {
+	BUILDER_API_NIL = "nil"
+}
 
 --- Registers a builder api for a class.
 --- The attributes are set as private variables with "_" before the variable name 
 --- and the builder functions are named like the attribute.
+--- Nil values have to be replaced with CpObjectUtil.BUILDER_API_NIL !!
 ---@param class table
 ---@param attributesToDefault table<attributeName, any>
 function CpObjectUtil.registerBuilderAPI(class, attributesToDefault)
 	for attributeName, default in pairs(attributesToDefault) do 
+		if default == CpObjectUtil.BUILDER_API_NIL then 
+			default = nil
+		end
 		--- Applies the default value to the private variable
 		class["_" .. attributeName] = default
 		--- Creates the builder functions/ setters with the public variable name

scripts/ai/PathfinderController.lua

@@ -117,16 +117,16 @@ PathfinderControllerContext.attributesToDefaultValue = {
 	["offFieldPenalty"] = 7.5,
  	["useFieldNum"] = false,
 	-- Pathfinder nodes in this area have a prohibitive penalty (2000)
-	["areaToAvoid"] = nil,
+	["areaToAvoid"] = CpObjectUtil.BUILDER_API_NIL,
 	["allowReverse"] = false,
-	["vehiclesToIgnore"] = nil,
+	["vehiclesToIgnore"] = CpObjectUtil.BUILDER_API_NIL,
 	-- If false, as we reach the maximum iterations, we relax our criteria to reach the goal: allow for arriving at
 	-- bigger angle differences, trading off accuracy for speed. This usually results in a direction at the goal
 	-- being less then 30º off which in many cases isn't a problem.
 	-- Otherwise, for example when a combine self unloading must accurately find the trailer, set this to true.
 	["mustBeAccurate"] = false,
 	-- No fruit penalty in this area (e.g. when we know the goal is in fruit but want to avoid fruit all the way there)
-	["areaToIgnoreFruit"] = nil
+	["areaToIgnoreFruit"] = CpObjectUtil.BUILDER_API_NIL
 }
 
 function PathfinderControllerContext:init(vehicle, numRetries)