feat(core+frontend): enhance SyncEvent model and integrate sync handling in BewerbViewModel

- **Core Updates:**
  - Expanded `SyncEvent` model with additional fields (`eventId`, `sequenceNumber`, `originNodeId`, `createdAt`, `checksum`, `schemaVersion`) for improved event tracking and validation.
  - Updated event classes (`PingEvent`, `PongEvent`, `DataChangedEvent`, `DataRequestEvent`) to align with the extended `SyncEvent`.

- **Frontend Enhancements:**
  - Enhanced `BewerbViewModel` to handle sync events (`PingEvent`, `DataChangedEvent`) and observe connected peers using `SyncManager`.
  - Added support for

frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/sync/SyncEvent.kt

@@ -7,8 +7,12 @@ import kotlinx.serialization.Serializable
  */
 @Serializable
 sealed interface SyncEvent {
-    val timestamp: Long
-    val senderId: String
+    val eventId: String
+    val sequenceNumber: Long
+    val originNodeId: String
+    val createdAt: Long
+    val checksum: String
+    val schemaVersion: Int
 }
 
 /**
@@ -16,8 +20,12 @@ sealed interface SyncEvent {
  */
 @Serializable
 data class PingEvent(
-    override val timestamp: Long,
-    override val senderId: String
+    override val eventId: String,
+    override val sequenceNumber: Long,
+    override val originNodeId: String,
+    override val createdAt: Long,
+    override val checksum: String = "",
+    override val schemaVersion: Int = 1
 ) : SyncEvent
 
 /**
@@ -25,8 +33,12 @@ data class PingEvent(
  */
 @Serializable
 data class PongEvent(
-    override val timestamp: Long,
-    override val senderId: String
+    override val eventId: String,
+    override val sequenceNumber: Long,
+    override val originNodeId: String,
+    override val createdAt: Long,
+    override val checksum: String = "",
+    override val schemaVersion: Int = 1
 ) : SyncEvent
 
 /**
@@ -34,11 +46,16 @@ data class PongEvent(
  */
 @Serializable
 data class DataChangedEvent(
-    override val timestamp: Long,
-    override val senderId: String,
-    val entityType: String,
-    val entityId: String,
-    val operation: String // "CREATED", "UPDATED", "DELETED"
+    override val eventId: String,
+    override val sequenceNumber: Long,
+    override val originNodeId: String,
+    override val createdAt: Long,
+    override val checksum: String = "",
+    override val schemaVersion: Int = 1,
+    val aggregateType: String,
+    val aggregateId: String,
+    val eventType: String, // "CREATED", "UPDATED", "DELETED"
+    val payload: String // Base64 oder JSON String
 ) : SyncEvent
 
 /**
@@ -46,8 +63,12 @@ data class DataChangedEvent(
  */
 @Serializable
 data class DataRequestEvent(
-    override val timestamp: Long,
-    override val senderId: String,
-    val entityType: String,
-    val entityId: String
+    override val eventId: String,
+    override val sequenceNumber: Long,
+    override val originNodeId: String,
+    override val createdAt: Long,
+    override val checksum: String = "",
+    override val schemaVersion: Int = 1,
+    val aggregateType: String,
+    val aggregateId: String
 ) : SyncEvent

frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/sync/SyncManager.kt

@@ -28,9 +28,7 @@ class SyncManager(
                 discovered.forEach { service ->
                     val peerKey = "${service.host}:${service.port}"
                     if (!knownPeers.contains(peerKey)) {
-                        // Prüfen, ob wir es nicht selbst sind (einfacher Check über Port,
-                        // in Realität über eine Node-ID im Metadata)
-                        // TODO: Node-ID Vergleich
+                        // TODO: Node-ID Vergleich (Selbst-Verbindung vermeiden)
                         println("[SyncManager] Neuer Peer entdeckt: $peerKey. Verbinde...")
                         syncService.connectToPeer(service.host, service.port)
                         knownPeers.add(peerKey)
@@ -41,6 +39,16 @@ class SyncManager(
         }
     }
 
+    fun getConnectedPeers() = syncService.connectedPeers
+
+    fun broadcastEvent(event: SyncEvent) {
+        scope.launch {
+            syncService.broadcastEvent(event)
+        }
+    }
+
+    fun getIncomingEvents() = syncService.incomingEvents
+
     fun stop() {
         scope.cancel()
         discoveryService.stopDiscovery()