[CLI] Have an automated CLI schema to ensure it doesn't make random commands

Claude with the MCP ended up making this command

```sh
aptos move compile --check
```

And then retried as

```sh
aptos move compile
```

Maybe we can use the generated code completions as a schema to know what commands are valid or not

```sh
aptos config generate-shell-completions --shell zsh --output-file completions
```