Add "Toggle comment" key command (#321)

Co-authored-by: Ben Jervis <bjervis@seek.com.au>
Co-authored-by: GitButler <gitbutler@gitbutler.com>
Co-authored-by: Adam Skoufis <askoufis@users.noreply.github.com>

.changeset/tender-spiders-compete.md

@@ -0,0 +1,8 @@
+---
+'playroom': minor
+---
+
+Add keybinding to toggle comment syntax for the current selection.
+
+Pressing <kbd>Cmd</kbd> + <kbd>/</kbd> (or, on Windows, <kbd>Ctrl</kbd> + <kbd>/</kbd>) will toggle comment syntax for the currently selected text.
+If no text is selected, the line the cursor is on will toggle comment syntax.