Give notes if a results could have been cut while processing a query

MariaDB has variables to limit memory usage, like group_concat_max_len, max_digest_length, max_sort_length etc.

If the length of a string is longer than one of the above constraints (which is depending on context), the string will be silently cut.
In many cases the cut will not have any effect (like cutting the end of a long unique string when sorting) , but it would be good to inform the user that a cut was done.

The task is to give a 'note' in the cases this happens so that the user will know that if they would repeat the query with 'infinite memory' the answer could be different.