Fix server/client component boundary issue with reasonColor/reasonLabel helper functions by moving them to shared utils

src/app/dashboard/admin/abwesenheiten/absence-table.tsx

@@ -3,6 +3,7 @@
 import { useState } from "react";
 import { AbsenceReason } from "@prisma/client";
 import { CalendarDays, Circle, MessageSquareText, UserRound } from "lucide-react";
+import { reasonColor, reasonLabel } from "@/lib/absence-utils";
 
 import { Badge } from "@/components/ui/badge";
 import {
@@ -176,17 +177,7 @@ function getInitials(name: string) {
     .toUpperCase();
 }
 
-export function reasonLabel(reason: AbsenceReason) {
-  if (reason === AbsenceReason.ILLNESS) return "Krank";
-  if (reason === AbsenceReason.VACATION) return "Urlaub";
-  return "Sonstiges";
-}
 
-export function reasonColor(reason: AbsenceReason) {
-  if (reason === AbsenceReason.ILLNESS) return "var(--danger)";
-  if (reason === AbsenceReason.VACATION) return "var(--warn)";
-  return "var(--accent)";
-}
 
 export function formatDateRange(startDate: string, endDate: string) {
   const start = new Date(`${startDate}T00:00:00`);