Logging: Write versions from both app and extension

Signed-off-by: Roopesh Chander <roop@roopc.net>

WireGuard/Shared/Logging/Logger.swift

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: MIT
 // Copyright © 2018 WireGuard LLC. All Rights Reserved.
 
+import Foundation
 import os.log
 
 class Logger {
@@ -32,6 +33,15 @@ class Logger {
     }
 }
 
+func wg_log_versions_to_file() {
+    var appVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "Unknown version"
+    if let appBuild = Bundle.main.infoDictionary?["CFBundleVersion"] as? String {
+        appVersion += " (\(appBuild))"
+    }
+    let goBackendVersion = WIREGUARD_GO_VERSION
+    file_log(message: "App version: \(appVersion); Go backend version: \(goBackendVersion)")
+}
+
 func wg_log(_ type: OSLogType, staticMessage msg: StaticString) {
     // Write to os log
     os_log(msg, log: OSLog.default, type: type)