feat: Allow skip check if dir is full or empty for icons

Nobody has claimed this yet.

I use Borg Backup. It can mount its repo with FUSE, and then you get a mountpoint directory with Borg archives as subdirs. However, accessing each directory is very time consuming, it takes me about a minute to `cd` or `ls` into one of them.

By using `eza --icons=always` when in the main mountpoint, `eza` freezes and even seems impossible to `ctrl+c`. I strongly suspect this is due to determining for each dir if a dir is empty or not, as they use different icons.

It would be beneficial to add a flag to `eza` that allows to skip this single check, and use the same icon for full and empty dirs. This would allow use cases like this to keep it aliased to `eza --icons=auto ...` while avoiding such performance penalties, by sacrificing a minor detail in dir icon.

Start by tracing eza's icon rendering path and the directory emptiness check described in the issue. Determine where a command-line option would control that check, then verify that full and empty directories can share an icon when it is disabled and that existing icon behavior remains unchanged.

Written by the indexing model from the issue text.