fix(ini): Support plus sign prefix in INI integer parse (#2576)

Author: xezon

Core/GameEngine/Source/Common/INI/INI.cpp

@@ -1618,8 +1618,17 @@ void INI::initFromINIMulti( void *what, const MultiIniFieldParse& parseTableList
 template <typename Type>
 Type scanType(std::string_view token)
 {
-	// TheSuperHackers @info std::from_chars cannot parse "-1" as uint32 so the result needs to be int64 for integers.
-	std::conditional_t<std::is_integral_v<Type>, Int64, Real> result{};
+	DEBUG_ASSERTCRASH(!token.empty(), ("token is not expected to be empty"));
+
+	// Unlike sscanf, std::from_chars cannot parse "+".
+	// Consume the plus symbol to accommodate custom ini files that have numbers prefixed with a plus.
+	if (token[0] == '+')
+	{
+		token.remove_prefix(1);
+	}
+
+	// Unlike sscanf, std::from_chars cannot parse "-" as unsigned integer.
+	std::conditional_t<std::is_integral_v<Type>, Int64, Type> result{};
 	const auto [ptr, ec] = std::from_chars(token.data(), token.data() + token.size(), result);
 
 	if (ec != std::errc{})