Add screenshots for code-line-numbers

Author: cwickham

docs/get-started/computations/images/positron-code-line-numbers-python.png

@@ -276,6 +276,18 @@ ggplot(mpg, aes(x = hwy, y = cty, color = cyl)) +
 ```
 :::
 
+:::{.panel-tabset group="language"}
+
+## R 
+
+![](images/positron-code-line-numbers-r.png){.border fig-alt="Part of a rendered Quarto document with the title Quarto Computations. The document contains a code cell that has been expanded and shows line numbers."}
+
+## Python
+
+![](images/positron-code-line-numbers-python.png){.border fig-alt="Part of a rendered Quarto document with the title Quarto Computations. The document contains a code cell that has been expanded and shows line numbers."}
+
+:::
+
 The options available for code cells depend on the engine used to execute the code cells.
 You can read more about how Quarto chooses an engine in [Engine Binding](/docs/computations/execution-options.qmd#engine-binding).