feat: #3631112 Show Date Published as radio buttons in the search filter rail

Follow-up to #3631112 (issue: https://www.drupal.org/i/3631112).

Date Published in the search filter rail is now a list of radio buttons instead of a select, like the facets above it and like the search page design of the other Vardot site templates. Only the date filter widget changes (group_info.widget: radios on the date block); the labels ("Any time", "Past …") and the filtering stay the same.

Tested on a Varbase 11 site with Horizon Aid at 1440 and 390: the radios render with the theme radio component, choosing Past Week filters the results and keeps the keyword, no console errors.

Needs the vartheme_bs5_horizonaid MR for #3631109 (radio styling) merged first.

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