feat: Exclude/filter files based on attributes

It would be nice if there was a way to selectively filter out files based on their attributes. e.g. The possibility to only list read-only files, or (what would be the most useful aspect for me personally) exclude hidden system files without excluding 'normal' hidden files.

The issue names no files, tests, or entry points. Start by locating eza's existing file-selection and hidden-file handling, then determine how attribute filters should distinguish read-only files from hidden system files. Done means the command can selectively include or exclude these attributes without hiding ordinary files unintentionally.

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