Header cleanup.

src/Enum.hpp

@@ -5,6 +5,7 @@
 #include <vector>
 #include "MacroUtils.hpp"
 #include "StringView.hpp"
+#include <variant>
 
 #define ENUM_VALUE(x, value) x = value,
 #

src/String/StringView.hpp

@@ -1,12 +1,11 @@
 #ifndef ARBUTILS_STRINGVIEW_HPP
 #define ARBUTILS_STRINGVIEW_HPP
 
-#include <atomic>
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
 #include <memory>
-#include <string>
+#include <string_view>
 #include "BasicStringView.hpp"
 
 #if WINDOWS