[fix] Support exclusively special characters in component filenames

[danedavid]

Fixes #7143.

This PR supports special characters like @, &, ~ by not removing the leading/trailing _ in a filename if it's the only character in the function get_name_from_filename.

[benmccann]

It seems potentially problematic that we could have two files end up with the same component names?

[danedavid]

@benmccann Should we add some kind of increasing number sequence in such cases?

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