Reject trailing arguments / missing params?

Just a minor nit: would be nice from a ux perspective if this failed:

```
poc-witness@www:~$ ~/go/bin/witnessctl list-logs ~/.local/share/litewitness/database && echo "hi"
hi
```

(Noticed this when omitting `-db` by mistake.

Start at the witnessctl list-logs command entry point and reproduce the shown invocation, including the omitted -db case. Trace how trailing and missing arguments are handled; done means both invalid forms fail instead of continuing to execute the following shell command.

Written by the indexing model from the issue text.