Add option to list the nth log? eg: second last log

[realshovanshah]

Using llm logs -n (or llm logs -r) I'm able to lists the last log. Similarly, accessing the second or third last log - or even the nth log - is a natural use case.

Hope I've not missed an obvious way to achieve this. The contributors have probably already thought of implementing this, but I wanted to ask if this is something that'd be added in the short-term?