`chalk foo` should error unless `foo` is a valid command

## Example

Run chalk with an invalid command name, such as:

```shell
chalk inserrt my_artifact
```

## Expected behavior

Produce an error, saying that `inserrt` is not a valid command name.

For example, in other tools:

```console
$ git checkoutt main
git: 'checkoutt' is not a git command. See 'git --help'.

The most similar command is
checkout
```

```console
$ docker buildd
docker: 'buildd' is not a docker command.
See 'docker --help'
```

## Observed behavior

Exits with an exit status of 0, after searching the docs for the invalid command:

```console
$ chalk inserrt my_artifact
Searching Documentation For Terms: Inserrt, My_Artifact
No Matches Found In Command-Line Flag Documentation
No Matches In Configuration Variables
No Matches In Found Metadata Key Docs
No Matches In Other Documents.
```

## Impact and discussion

A user may make a typo when adding chalk commands to scripts. Currently, this would cause unexpected behavior more quietly than it should.

I also do not expect `chalk foo` to search the docs for `foo`, and I can't think of a CLI tool that does that. I think that searching the docs should be explicit.

No source file or test is named in the issue. Reproduce the `chalk inserrt my_artifact` command, then trace the CLI command-dispatch entry point to see why an unknown command reaches documentation search. Done means an invalid command produces a clear error instead of searching documentation or exiting successfully.

Written by the indexing model from the issue text.