document ContainsAll trait

Author: SizzinSeal

include/common/result_impl.hpp

@@ -157,6 +157,12 @@ concept InPack = (std::same_as<std::remove_cvref_t<T>, Ts> || ...);
 template<typename... Ts>
 struct type_pack {};
 
+/**
+ * @brief Check if all the types in the second type pack are present in the first type pack
+ *
+ * @tparam PackA
+ * @tparam PackB
+ */
 template<typename PackA, typename PackB>
 concept ContainsAll = []<typename... As>(type_pack<As...>) {
     return []<typename... Bs>(type_pack<Bs...>) {