Allows users to customize the OpenTelemetry service name instead of using the hardcoded default `lighthouse`. Defaults to 'lighthouse-bn' for beacon node, 'lighthouse-vc' for validator client, or 'lighthouse' for other subcommands.
This is useful when analysing traces from multiple nodes, see Grafana screenshot below with service name overrides in Kurtosis (`ethereum-package` PR: https://github.com/ethpandaops/ethereum-package/pull/1160):
<img width="1148" height="627" alt="image" src="https://github.com/user-attachments/assets/7e875639-10f7-4756-837f-2006fa4b12e0" />