[feature]: hide code editor, support #| context: output

[mattijn]

Feature Description

Thank you for developing this very interesting quarto extension!

The feature request that I like to raise is to have a context setting that disables the code editor, but runs the code cell upon opening the website.

After reading a bit more in the qwebr documentation, I find out that this requested setting is defined there under Run Options:

So the proposed option would be:

```{pyodide-python}
#| context: output

x = 1
x
```

This request is similar to #17, but as it is another context setting, I thought I would raise it as a separate issue.

My end goal is to implement this proof of concept where two Vega-Altair charts (as JupyterChart components) are interacting with each other.

I've tried to do similar using the quarto-stlite extension (link), but did not yet succeed either.

Thanks again for working on this!