Split comparators into source files

src/kyut/Comparator.hpp

+#ifndef INCLUDE_kyut_Comparator_hpp
+#define INCLUDE_kyut_Comparator_hpp
+
+#include <wasm.h>
+
+namespace wasm {
+    [[nodiscard]] bool operator<(const Literal &a, const Literal &b);
+    [[nodiscard]] bool operator<(const Expression &a, const Expression &b);
+    [[nodiscard]] bool operator<(const ExpressionList &a, const ExpressionList &b);
+} // namespace wasm
+
+#include "Comparator.inl.hpp"
+
+#endif // INCLUDE_kyut_Comparator_hpp