feat(employees): default minGapDays to 14, robust ID fallback

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

js/data.js

@@ -1,3 +1,18 @@
+function generateId() {
+  if (typeof crypto !== 'undefined' && typeof crypto.randomUUID === 'function') {
+    return crypto.randomUUID();
+  }
+  if (typeof crypto !== 'undefined' && typeof crypto.getRandomValues === 'function') {
+    const b = new Uint8Array(16);
+    crypto.getRandomValues(b);
+    b[6] = (b[6] & 0x0f) | 0x40;
+    b[8] = (b[8] & 0x3f) | 0x80;
+    const h = [...b].map(x => x.toString(16).padStart(2, '0'));
+    return `${h.slice(0,4).join('')}-${h.slice(4,6).join('')}-${h.slice(6,8).join('')}-${h.slice(8,10).join('')}-${h.slice(10,16).join('')}`;
+  }
+  return Date.now().toString(36) + Math.random().toString(36).slice(2, 10);
+}
+
 function parseSettings(raw) {
   const n = raw?.moderatorsPerDay;
   const valid = Number.isInteger(n) && n >= 1 && n <= 5;
@@ -40,14 +55,14 @@ export function createEmployee(name) {
   const trimmed = (name ?? '').trim();
   if (!trimmed) throw new Error('Mitarbeitername darf nicht leer sein');
   return {
-    id: crypto.randomUUID(),
+    id: generateId(),
     name: trimmed,
     constraints: {
       neverDays: [],
       lowPriorityDays: [],
       onlyDays: [],
       maxPerMonth: null,
-      minGapDays: 0,
+      minGapDays: 14,
       vacations: []
     }
   };