fix: 修复 handleDisconnect 在 disconnect 失败时不触发 .disconnected 事件的问题

Sources/Nats/NatsConnection.swift

@@ -989,11 +989,13 @@ class ConnectionHandler: ChannelInboundHandler {
             promise.futureResult.whenComplete { result in
                 do {
                     try result.get()
-                    self.fire(.disconnected)
                 } catch {
                     // 降级为 debug：网络断开时 TLS 无法完成正常关闭握手是预期行为
                     logger.debug("Connection closed with error (will reconnect): \(error)")
                 }
+                // 无论成功还是失败，都要触发 .disconnected 事件
+                // 这样上层才能感知到连接已断开
+                self.fire(.disconnected)
                 // Only start reconnect after disconnect is complete
                 self.handleReconnect()
             }