fix: undefined check for user input values

Author: micwallace

javascript/engine-js/src/tokenScript/data/function/Argument.ts

@@ -174,7 +174,7 @@ export class Argument extends AbstractDependencyBranch implements IArgument {
 			// local-ref can be used to get attributes defined by a view that aren't explicitly defined in the tokenscript
 			const value = this.tokenScript.getViewController().getUserEntryValue(this.localRef, tokenContext?.selectedTokenId ?? "-1");
 
-			if (!value){
+			if (value === undefined){
 				throw e;
 			}