fix: showMed/showLow undefined JS error

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

static/interface.html

@@ -1913,6 +1913,9 @@
     }
 
     // ── Filters ───────────────────────────────────────────────────────────────
+    let showMed = true;
+    let showLow = true;
+
     function applyFilters() {
       const query = (document.getElementById('termFilter').value || '').toLowerCase().trim();
       document.querySelectorAll('.pred-row').forEach(row => {