swift: fix proxy settings

updates tailscale/tailscale#15802

Updates the proxy settings.  These more modern constants
work with both macOS and iOS, for both localapi and
NSURLConnection socks to tailnet URLs

swift/Examples/TailscaleKitHello/HelloFromTailscale/HelloFromTailscaleApp.swift

@@ -5,7 +5,7 @@ import SwiftUI
 
 @main
 struct HelloFromTailscaleApp: App {
-    let manager = HelloManager()
+    let manager = HelloManager.shared
 
     var body: some Scene {
         WindowGroup {

swift/Examples/TailscaleKitHello/HelloFromTailscale/HelloManager.swift

@@ -25,6 +25,8 @@ protocol Dialer: Actor {
 actor HelloManager: Dialer {
     var node: TailscaleNode?
 
+    static let shared = HelloManager()
+
     let logger = Logger()
 
     let config: Configuration
@@ -110,7 +112,8 @@ actor HelloManager: Dialer {
 
             // Request a resource from the tailnet...
             let url = URL(string: Settings.tailnetServer)!
-            let req = URLRequest(url: url)
+            var req = URLRequest(url: url)
+
 
             let (data, _) = try await session.data(for: req)
             await setMessage("\(Settings.tailnetServer) says:\n \(String(data: data, encoding: .utf8) ?? "(crickets!)")")

swift/TailscaleKit/URLSession+Tailscale.swift

@@ -20,21 +20,16 @@ public extension URLSessionConfiguration {
         }
 
 
-        var config: [CFString: Any] = [
+        let config: [CFString: Any] = [
             kCFProxyTypeKey: kCFProxyTypeSOCKS,
             kCFProxyUsernameKey: "tsnet",
             kCFProxyPasswordKey: proxyConfig.proxyCredential,
-            kCFNetworkProxiesHTTPEnable: true,
-            kCFNetworkProxiesHTTPProxy: ip,
-            kCFNetworkProxiesHTTPPort: port,
+            kCFProxyHostNameKey: ip,
+            kCFProxyPortNumberKey: port
         ]
 
-        #if os(macOS)
-        config[kCFNetworkProxiesHTTPSEnable] = true
-        #endif
-
         self.connectionProxyDictionary = config
-
+        
         return proxyConfig
     }