Add new AIM/LLM aggregator

[bizob2828]

Description

Provide a new aggregator to enqueue LLM events that sends to collector custom_event_data method

Acceptance Criteria

As an agent engineer, they should be able to enqueue a new common event that is sent to the custom_event_data method but is controlled separately from the custom events currently defined. It should have its own aggregator, and configuration.

Additional context

The configuration has not been approved for the new AI monitoring events. We can initially deliver this feature with the same configurations as custom events and another story(#1982) will be to define the new configuration.

[workato-integration]

https://new-relic.atlassian.net/browse/NR-220933