refactor: Fix macOS standalone application

Library/Network/UserServiceEndpointRegistry.swift

@@ -0,0 +1,28 @@
+#if os(macOS)
+    import Foundation
+
+    final class UserServiceEndpointRegistry {
+        static let shared = UserServiceEndpointRegistry()
+
+        private let lock = NSLock()
+        private var endpoint: NSXPCListenerEndpoint?
+
+        func update(_ endpoint: NSXPCListenerEndpoint) {
+            lock.lock()
+            self.endpoint = endpoint
+            lock.unlock()
+        }
+
+        func clear() {
+            lock.lock()
+            endpoint = nil
+            lock.unlock()
+        }
+
+        func get() -> NSXPCListenerEndpoint? {
+            lock.lock()
+            defer { lock.unlock() }
+            return endpoint
+        }
+    }
+#endif