Throw explicit error when there's a typo in the install command

[JQuezada0]

Relevant issue: https://github.com/cocktailpeanut/dalai/issues/371

When running npx dalai llama install [..] if you don't spell "llama" correctly you'll get an error that doesn't indicate what's failing

ERROR TypeError: Cannot read properties of undefined (reading 'home')
    at Dalai.install ($HOME/.npm/_npx/3c737cbb02d79cc9/node_modules/dalai/index.js:337:43)

This will just be a bit more explicit