Add a skeleton Bots service implementation

Description

This MR adds a skeleton Bots service implementation for use with RabbitMQ. Since none of the queue functionality exists yet, this doesn't actually function other than providing placeholder implementations of the various methods, as well as the instance-specific logic.

Validation

docker-compose -f docker-compose.rabbitmq.yml up --build

Ensure that the Bots service comes up successfully and reports that it would use the configured RabbitMQ endpoint (rabbitmq:5672).

Issues addressed

Closes #381 (closed)