Visually identify FLE2 collections in show collections

Visually identify FLE 2 encrypted collections in the output of “show collections” and group the internal FLE collections together similarly to what we do for Time Series collections.

Collections are identified by encryptedFields being present in the listCollections result, internal FLE collections start with enxcol_. by default.

https://github.com/mongodb-js/mongosh/blob/7509c0c1712feb859c512435ee7c7dcb1f3459d3/packages/cli-repl/src/format-output.ts#L126

https://github.com/mongodb-js/mongosh/blob/943239eb42e4011e8e666f72b4614da91da95b72/packages/shell-api/src/database.ts#L172