Fix the callers of GetEffectiveAttackRange's out-of-reach range

Follows db23584fc3 - the caller of GetEffectiveAttackRange's didn't
really use the NEVER_IN_RANGE result properly.
The C++ engine does not handle Infinity (treated as 0).
This also changes MoveToTargetAttackRange to explicitly try to get
closer if the parabolic range is not in range, but it seems like a flat
range could - on the assumption that once we get closer, the terrain
height difference is lower.

binaries/data/mods/public/simulation/components/Attack.js

@@ -572,7 +572,9 @@ Attack.prototype.GetRange = function(type)
  * for elevation and projectile physics where applicable.
  * @param {number} target - The target entity ID.
  * @param {string} type - The attack type.
- * @return {{ min: number, max: number }} - The min and max effective range.
+ * @return {{ min: number, max: number }} - The min and max effective range,
+ *	or { Infinity, 0 } if the target cannot be reached on a parabolic
+ *	trajectory given the current terrain height difference.
  */
 Attack.prototype.GetEffectiveAttackRange = function(target, type)
 {
@@ -931,6 +933,10 @@ Attack.prototype.PerformAttack = function(type, target)
 Attack.prototype.IsTargetInRange = function(target, type)
 {
 	const range = this.GetEffectiveAttackRange(target, type);
+	// Out of parabolic reach: GetEffectiveAttackRange returns { Infinity, 0 } in that case.
+	if (range.min > range.max)
+		return false;
+
 	return Engine.QueryInterface(SYSTEM_ENTITY, IID_ObstructionManager).IsInTargetRange(
 		this.entity, target, range.min, range.max, false);
 };

binaries/data/mods/public/simulation/components/UnitAI.js

@@ -5187,15 +5187,19 @@ UnitAI.prototype.MoveToTargetAttackRange = function(target, type)
 
 	const flatRange = cmpAttack.GetRange(type);
 	const effectiveRange = cmpAttack.GetEffectiveAttackRange(target, type);
-	if (effectiveRange.max < 0)
-		return false;
+
+	// Out of parabolic range: assume the terrain height difference is to blame,
+	// and close in to reassess from there.
+	if (effectiveRange.min > effectiveRange.max)
+		return cmpUnitMotion.MoveToTargetRange(target, flatRange.min,
+			Math.max(flatRange.min, flatRange.max / 2));
 
 	// The parabola changes while walking so be cautious:
 	const guessedMaxRange = effectiveRange.max > flatRange.max ?
 		(flatRange.max + effectiveRange.max) / 2 :
 		effectiveRange.max;
 
-	return cmpUnitMotion && cmpUnitMotion.MoveToTargetRange(target, effectiveRange.min, guessedMaxRange);
+	return cmpUnitMotion.MoveToTargetRange(target, effectiveRange.min, guessedMaxRange);
 };
 
 UnitAI.prototype.MoveToTargetRangeExplicit = function(target, min, max)