Help inconsistencies in focus modify

```
$ focus past --help
Usage: focus past <list|add|modify|delete>
$ focus past modify 5
✅ Session 5 updated.
$ focus past modify 5 --help
✅ Session 5 updated.
$ focus past modify --help
Error: in prepare, incomplete input
$ focus past modify
Usage: focus past modify <id> [project] [start] [end]

```