relay: fix relays refusing to reconnect after initial connect fails

When isConnecting gets stuck (e.g. from silenced error 57 or lost
WebSocket events), reconnect() would bail out permanently. Instead of
unconditionally blocking on isConnecting, allow reconnect if the
connection attempt has gone stale (>5s with no socket response).

Closes: https://github.com/damus-io/damus/issues/3774

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

damus/Core/Nostr/RelayConnection.swift

@@ -114,7 +114,7 @@ final class RelayConnection: ObservableObject {
             guard let self else {
                 return
             }
-            
+
             if err == nil {
                 self.last_pong = .now
                 Log.info("Got pong from '%s'", for: .networking, self.relay_url.absoluteString)
@@ -214,7 +214,7 @@ final class RelayConnection: ObservableObject {
                 return
             }
             if nserr.domain == NSURLErrorDomain && nserr.code == -999 {
-                // these aren't real error, it just means task was cancelled
+                // these aren't real errors, it just means task was cancelled
                 return
             }
             DispatchQueue.main.async {
@@ -237,9 +237,9 @@ final class RelayConnection: ObservableObject {
     }
     
     func reconnect() {
-        guard !isConnecting && !isDisabled else {
-            self.log?.add("Cancelling reconnect, already connecting")
-            return  // we're already trying to connect or we're disabled
+        guard !isDisabled else {
+            self.log?.add("Cancelling reconnect, relay is disabled")
+            return
         }
 
         guard !self.isConnected else {
@@ -247,6 +247,17 @@ final class RelayConnection: ObservableObject {
             return
         }
 
+        // If we're already connecting, only force a reconnect if the
+        // attempt has gone stale (>5s with no response from the socket)
+        if isConnecting {
+            let elapsed = Date.now.timeIntervalSince1970 - last_connection_attempt
+            guard elapsed > 5 else {
+                self.log?.add("Cancelling reconnect, already connecting")
+                return
+            }
+            self.log?.add("Stale connection detected, forcing reconnect")
+        }
+
         disconnect()
         connect()
         log?.add("Reconnecting...")