refs #19737 [fid_bbi] record sidebar with ul/li

* introduces initial 2 column styling
* revises column SCSS to use existing BBI styles
* adds correct headings
* turns result list sidebar tools into ul too

* Sidefacets as uls
** fine-tunes two-column layout
** introduces two-column layout to result list sidebar
** introduces heading to result list sidebar
** corrects heading hierarchy in result list sidebar

* sidebar toolbars as ULs
** fixes look across all media queries
** fine-tunes look on any device below 400px

* switch confounded translations for toolbar headlines

co-authored by: Gregor Gawol <gawol@ub.uni-leipzig.de>
co-authored by: Robert Lange <robert.lange@uni-leipzig.de>