Refactor event retrieval logic: Implement server-side filtering for past events based on user preference, enhancing performance and simplifying client-side code. Update API call in EventManagement component to include past events parameter.

src/content/admin/EventManagement.vue

@@ -83,26 +83,7 @@ export default {
     filteredEvents() {
       let filtered = this.events;
 
-      // Filter vergangene Events aus
-      if (!this.showPastEvents) {
-        const today = new Date();
-        today.setHours(0, 0, 0, 0);
-        
-        filtered = filtered.filter(event => {
-          // Events mit Wochentag (ohne festes Datum) immer anzeigen
-          if (event.dayOfWeek !== null && event.dayOfWeek !== undefined && !event.date) {
-            return true;
-          }
-          // Events mit Datum: nur zukünftige oder heutige anzeigen
-          if (event.date) {
-            const eventDate = new Date(event.date);
-            eventDate.setHours(0, 0, 0, 0);
-            return eventDate >= today;
-          }
-          // Events ohne Datum und ohne Wochentag anzeigen
-          return true;
-        });
-      }
+      // Vergangenheitsfilter erfolgt serverseitig (GET /events?includePast=1)
 
       // Suchfilter anwenden
       if (this.searchQuery.trim()) {
@@ -121,6 +102,11 @@ export default {
       return filtered;
     }
   },
+  watch: {
+    showPastEvents() {
+      this.fetchData();
+    }
+  },
   async created() {
     await this.fetchData();
     this.hasNewsletterPreview = !!localStorage.getItem('newsletter_import_last_result');
@@ -176,7 +162,7 @@ export default {
     async fetchData() {
       try {
         const [eventResponse, institutionResponse, eventPlaceResponse, contactPersonResponse, eventTypeResponse] = await Promise.all([
-          axios.get('/events'),
+          axios.get('/events', { params: { includePast: this.showPastEvents ? 1 : 0 } }),
           axios.get('/institutions'),
           axios.get('/event-places'),
           axios.get('/contact-persons'),