Startify Does Not Open Directory When Giving One as a Bookmark

I am having an issue where I have given all of my bookmarks as directories, but when I select them `neovim` just opens an empty buffer. Does startify work with directories? If it helps here is my configuration.

```
----------------
--- Startify ---
----------------
-- Set the startify header.
plugin.startify_custom_header = {
'',
'',
' ██ ',
' ░░ ',
' ███████ █████ ██████ ██ ██ ██ ██████████ ',
' ░░██░░░██ ██░░░██ ██░░░░██░██ ░██░██░░██░░██░░██',
' ░██ ░██░███████░██ ░██░░██ ░██ ░██ ░██ ░██ ░██',
' ░██ ░██░██░░░░ ░██ ░██ ░░████ ░██ ░██ ░██ ░██',
' ███ ░██░░██████░░██████ ░░██ ░██ ███ ░██ ░██',
' ░░░ ░░ ░░░░░░ ░░░░░░ ░░ ░░ ░░░ ░░ ░░ ',
'',
'',
}

-- Set the bookmarked list.
plugin.startify_bookmarks = {
{ c = '~/.config' },
{ C = '~/dox/dev/misc/dotfiles' },
{ w = '~/dox/dev/core-software/working-projects' },
{ f = '~/dox/dev/core-software/finished-projects' },
}

-- Ser the list order.
plugin.startify_lists = {
{ type = 'files', header = { ' Most Recently Used' } },
{ type = 'bookmarks', header = { ' Bookmarks' } },
}
```

Reproduce the empty-buffer behavior using the Startify configuration and directory bookmarks shown in the issue. Then trace how bookmark paths are opened and check the existing tests or documentation for directory handling. Done means directory bookmarks open their directories in Neovim, with a regression check if the project has a suitable test location.

Written by the indexing model from the issue text.