Revamp asb:Listener/asb:Service based implementation

[ayeshLK]

Purpose

$subject

Fixes: #6495

Proposal: ballerina-platform/ballerina-library#6508

Examples

With this PR listener-service based async-message consuming functionality will be revamped.

import ballerinax/asb;

listener asb:Listener asbListener = check new (
    connectionString = "<connection-string>",
    entityConfig = {
        queueName: "<queue-name>"
    },
    autoComplete = false
);

service asb:Service on asbListener {

    isolated remote function onMessage(asb:Message message, asb:Caller caller) returns error? {
        // implement the message processing logic here
    }

    isolated remote function onError(asb:MessageRetrievalError 'error) returns error? {
        // implement error handling logic here
    }
}

Checklist

• Linked to an issue
• Updated the specification
• Updated the changelog
• Added tests
• Checked native-image compatibility

[NipunaRanasinghe]

LGTM