Allow hiding directories containing no filter results

[przepompownia]

Hey,

Sometimes I'd like to filter some tree using nvim-tree (usually outside the current project where I am used to Telescope). I didn't found how to hide directories that contains no visible nodes (especially with applied some filter). For example, like in #2495, after filtering with wat query (and optionally hiding hidden files), we see lots of directories that lead to no result.

It would be nice to can hide them using keymap and configuration (at least when the filter query is not empty) and optionally apply group_empty on visible ones, if enabled.

[alex-courtis]

It sounds like we want the live filter to behave like the others e.g. git clean: hide empty directories and collapse.

Let's follow in #2495 and see how we go.

I'm happy to class this as a bug as the current functionality is not consistent nor useful.