fix: use typed category field instead of Record cast

frontend/src/components/deadlines/DeadlineCalculator.tsx

@@ -101,7 +101,7 @@ export function DeadlineCalculator() {
                 const seen = new Set<string>();
                 for (const pt of types) {
                   const j = pt.jurisdiction ?? "Sonstige";
-                  const c = (pt as Record<string, unknown>).category as string ?? "hauptverfahren";
+                  const c = pt.category ?? "hauptverfahren";
                   const key = `${j}::${c}`;
                   if (!seen.has(key)) {
                     seen.add(key);