`chalk help validcommand --valid-flag` shouldn't search docs

## Example

Run with latest chalk release (v0.3.3) or commit (cf9ebf8476bf3e3a2399512673e2ccc12dbb8aeb):

```
chalk help insert --no-color
```

## Expected behavior

Prints the help for `insert` without color, which is what `chalk insert --help --no-color` does.

## Observed behavior

Prints the results of a documentation search for `insert` and `--no-color`:

```text
Searching Documentation For Terms: Insert, --No-Color
[large amount of output]
```

## Other examples

```
chalk help commands --no-pager
```

## Related issues

This is similar to https://github.com/crashappsec/chalk/issues/172

Reproduce the issue with `chalk help insert --no-color` and `chalk help commands --no-pager`, comparing both with the corresponding direct help commands. Trace the CLI handling of `help` arguments and flags. Done means valid command help is shown with the requested flag behavior instead of triggering a documentation search.

Written by the indexing model from the issue text.