Wait for the server's tailnet peer before connecting at app startup

mac/Sources/Byre/Startup.swift

@@ -198,7 +198,7 @@ final class Connection {
 
     private func start() async {
         let old = store
-        while !stopped, !Tailnet.shared.running {
+        while !stopped, !Tailnet.shared.reachable(origin) {
             try? await Task.sleep(for: .milliseconds(500))
         }
         while !stopped, !(await attempt(old)) {
@@ -252,6 +252,7 @@ final class Connection {
             Notifier.shared.deliver()
             return true
         } catch {
+            log.notice("connect \(self.origin.absoluteString, privacy: .public) failed: \(errorText(error), privacy: .public); \(tailnetNode.peerState(self.origin.host()!), privacy: .public)")
             await store.stop()
             if !stopped {
                 phase = .failed(explain(error, origin))