Add more visibility for the ability to 'Add Sum to Internal Events'

Problem

Following the introduction of the possibility to Add sums to internal events 🚀, which is a really useful addition. We do not have enough visibility for it since we do not have it documented and it is also missing in the CLI.

Desired Outcome

1. This change is well documented
2. Users are able to use this through the CLI

Potential Solution

Documentation Update Needed

• Yes
• No

How to verify

Further actions needed