Document port `5052:5052`mapping in the operator guide

[boulder225]

🎯 Problem to be solved

Several operators have encountered problems with Charon/Lighthouse, which are mostly resolved by mapping port 5052:5052 in the docker-compose.yml file under the Lighthouse configuration. This problem is persistent, especially with home validators. Operators are receiving errors resolved by exposing port 5052 on the Lighthouse Docker. This port mapping is not currently mentioned in the operator guide, leading to confusion and errors among new operators.

🛠️ Proposed solution

• [ ] Document the port mapping requirement and its purpose in the operator guide to assist new operators.

[OisinKyne]

This should be changed on CDVN and LCDVN rather than docs @boulder225