CLI Documentation Page

[BryceGattis]

Is your feature request related to a problem? Please describe.
As a new user approaching SPK, it would be helpful to see auto-generated CLI documentation that lists all CLI commands with the flags that they have so I'm aware of what commands are available and get a better picture of what SPK can do.

Describe the solution you'd like
New documentation page like the ones from Rez under this page

[rydrman]

possibly something like this could help: https://crates.io/crates/clap-markdown