fix: remove redundant query= param from filter-specific metadata links on TFE page

Clicking orientation, AP program, finality, year, format, or keyword links
on the TFE page was passing both a dedicated filter param AND a query=
param. The query= text search doesn't look at the filter columns
(orientation, ap_program, etc.), so the AND combination yielded zero
results when the filter value didn't appear in title/authors/etc fields.

Also fix the language link: it was passing language as query= which
searches only title/authors/etc, not the languages column. Now uses
the dedicated language= param (DB layer already supported it, and
collectSearchParams now collects it).

app/public/assets/css/repertoire.css

@@ -770,7 +770,6 @@
 /* ── Collapsible filter controls ─────────────────────────────────── */
 .search-filters-toggle {
   flex-shrink: 0;
-  border-bottom: 1px solid var(--border-secondary);
 }
 
 .search-filters-summary {