feat: implement connection micro service

Description

Connection manager implementation as a micro service. The service is closed behind gateway and only work with TCP.

Supported methods are:

1. create invitation
2. accept invitation
3. get connection by id
4. list connections

In additional a gateway service was introduced to handle user interactions. For sending http requests and receive event on a web socket. Agent consumer is adjusted too to handle the actual work. Small changes for configs, clients and etc are introduced.

Related issues

Creating API Gateway #11 (closed)

Testing

No tests are added.

Checklist

• I have updated the documentation (if necessary)
• I have added unit tests for new functionality (if applicable)
• My code follows the style guidelines of this project
• I have tested this code on my local machine before submitting this MR

Reviewers

Additional Notes

No additional notes.

Closes #8 (closed)