Refactoring getting the state/command handle

[tonynajjar]

Describe the solution you'd like
As proposed here #345 (comment), the idea is make a utility function to retrieve a state/command handle from the state/command interfaces.

Inputs of that function: interfaces vector, name to look for, interface name (type) to look for
Returns: std::optional

[github-actions]

This issue is being labeled as stale because it has been open 45 days with no activity. It will be automatically closed after another 45 days without follow-ups.