feat: crypto: Add basic AES keyslot manager

We loads keys from AppData/Alber/sysdata/aes_keys.txt.

NOTE: We do differ from other emulators by not hardcoding the generator key, it's the user responsibility to provide it in aes_keys.txt.

include/helpers.hpp

@@ -5,6 +5,8 @@
 #include <fstream>
 #include <iostream>
 #include <iterator>
+#include <sstream>
+#include <string>
 #include <type_traits>
 #include <utility>
 #include <vector>
@@ -164,6 +166,19 @@ namespace Helpers {
 		return std::bit_cast<To, From>(from);
 	}
 #endif
+
+	static std::vector<std::string> split(const std::string& s, const char c) {
+		std::istringstream tmp(s);
+		std::vector<std::string> result(1);
+
+		while (std::getline(tmp, *result.rbegin(), c)) {
+			result.emplace_back();
+		}
+
+		// Remove temporary slot
+		result.pop_back();
+		return result;
+	}
 };  // namespace Helpers
 
 // UDLs for memory size values