refactor(mechanics): Move random from ConditionSet to on-demand auto-…

…conditions (endless-sky#10836)

source/ConditionSet.cpp

@@ -19,7 +19,6 @@ this program. If not, see <https://www.gnu.org/licenses/>.
 #include "DataNode.h"
 #include "DataWriter.h"
 #include "Logger.h"
-#include "Random.h"
 
 #include <algorithm>
 #include <cmath>
@@ -160,9 +159,7 @@ namespace {
 		for(const string &str : side)
 		{
 			int64_t value = 0;
-			if(str == "random")
-				value = Random::Int(100);
-			else if(DataNode::IsNumber(str))
+			if(DataNode::IsNumber(str))
 				value = static_cast<int64_t>(DataNode::Value(str));
 			else
 			{

source/PlayerInfo.cpp

@@ -3952,6 +3952,14 @@ void PlayerInfo::RegisterDerivedConditions()
 		return true;
 	});
 
+	// A condition for returning a random integer in the range [0, 100).
+	auto &&randomProvider = conditions.GetProviderNamed("random");
+	auto randomFun = [](const string &name) -> int64_t
+	{
+		return Random::Int(100);
+	};
+	randomProvider.SetGetFunction(randomFun);
+
 	// A condition for returning a random integer in the range [0, input). Input may be a number,
 	// or it may be the name of a condition. For example, "roll: 100" would roll a random
 	// integer in the range [0, 100), but if you had a condition "max roll" with a value of 100,