feat: Add Gotify notification service and integrate it with error reporting and contact form actions, making error reporting methods asynchronous.

lib/services/notifications/notification-service.ts

@@ -0,0 +1,9 @@
+export interface NotificationOptions {
+  title: string;
+  message: string;
+  priority?: number;
+}
+
+export interface NotificationService {
+  notify(options: NotificationOptions): Promise<void>;
+}