improve async listen / signal flow with new interface

Testing api with Karate: mocks and queue implementation: Error TestRunner.testParallel:15 Multi threaded access requested by thread Thread[pool-1-thread-1,3,main] but is not allowed for language(s) js. is produced when try to consume a queue with multiple messages. Flow: Call a messageMock.feature :

Background:
* def QueueUtils = Java.type('mocks.QueueUtils')
* configure cors = true
* configure responseHeaders = { 'Content-Type': 'application/json' }

Scenario: pathMatches('/message') && methodIs('post')
* def response = read('../../responses/message/message.json')
* def responseStatus = 200
* QueueUtils.send(response.data, JSON.stringify(read('test.json')), 25)
* QueueUtils.send(response.data, JSON.stringify(read('test1.json')), 25)
* QueueUtils.send(response.data, JSON.stringify(read('test2.json')), 25)

From feature:

Scenario: Send message
* def QueueConsumer = Java.type('mocks.QueueConsumer')
* def port = karate.start('messageMock.feature').port
* url baseUrl + port
Given path '/message';
And request read('req.json')
When method post
Then status 200
* def queue = new QueueConsumer(response.data)
* def handler = function(msg){ karate.signal(msg) }
* queue.listen(karate.toJava(handler))
* listen 2000
* json response = listenResult
* print '### received:', listenResult
And match response == read('test.json')
* listen 2000
* json response1 = listenResult
* print '### received1:', listenResult
And match response1 == read('test1.json')
* listen 2000
* json response2 = listenResult
* print '### received2:', listenResult
And match response2 == read('test2.json')

The error message is given on line:

* json response = listenResult I am creating an issue as instructed in https://stackoverflow.com/questions/68377437/karate-api-test-testrunner-testparallel15-multi-threaded-access-requested-by-t

Example project(minimal, complete and verificable): example.zip

[ChavdarEmilovPagoNxt]

@ptrthomas Happy to help even if is a little one. Hopefully will be able to contribute more in the future! Thank you once again for all your help and for creating this amazing tool! Testing would not be the same without it.

[ptrthomas]

1.1.0 released