Support =ew= querying too

We support starts with by doing a value like `Jo*` when filtering strings. We should do the same for ends-with `*hn`, and warn someone if they try to do a contains `*oh*`. Showing some guidance (tooltip?) would be nice in the UI somewhere for the database filtering syntax supported. It could be by data type.

Locate the UI code that handles database string filtering and the existing `Jo*` starts-with behavior. Trace how filter syntax is parsed, then check the relevant UI tests or run the filtering flow to verify `*hn`, guidance for `*oh*`, and the proposed data-type-specific help are covered.

Written by the indexing model from the issue text.