R: Render plots at the correct size on high DPI devices

[seeM]

Steps to reproduce the issue:

Run this code in a Quarto document with a high DPI screen:

#| fig-width: 4
#| fig-height: 3
plot(1:10)

The plot will be really large:

Expected or desired behavior:

Plots should be at the requested sized. On high DPI screens, plots should be higher resolution. The image itself is correctly sized, but the metadata containing its width and height need to be included in the kernel response.

Were there any error messages in the UI, Output panel, or Developer Tools console?

No.