This PR adds a new result type: File
Python class: searx/result_types/file.py
Jinja template: searx/templates/simple/result_templates/file.html
CSS (less) client/simple/src/less/result_types/file.less
Class 'File' (singular) replaces template 'files.html' (plural). The renaming
was carried out because there is only one file (singular) in a result. Not to be
confused with the category 'files' where in multiple results can exist.
As mentioned in issue [1], the class '.category-files' was removed from the CSS
and the stylesheet was adopted in result_types/file.less (there based on the
templates and no longer based on the category).
[1] https://github.com/searxng/searxng/issues/5198
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
