harmonize font sizes

[ute]

Choose monaco editor font size according to surrounding div (editorDiv)

[coatless]

@ute I'm going to make this PR the "font-size" change one and, I'll switch #173 to focusing solely on global options. Is that okay?

[ute]

👍
Please go ahesd, I was initially shy to open two issues / PRs 😊

[coatless]

@ute no worries. We appreciate the PRs 😄 👍 💯

[coatless]

@ute I think the output size should largely be sync'd now with the code editor text size.

I added the above demo under docs/demos/qwebr-editor-options.qmd.

Though, given that bootstrap is defining a custom style on the pre tag, we won't be 100% in sync with a raw code cell.

Let me know what you think. If this is okay, we can close it out and move on to the next issue.

[coatless]

Going to fold this into main to add a few more options into the editor options demo.