Support inline 'Insert Anything' with AZERTY keyboard layouts on macOS

Originally filed here: https://github.com/rstudio/rstudio/issues/14824

If I understand correctly, if someone wants to trigger omni-completion within a line, they need to hold down the Mod (Command) key. So, on macOS, this would be Command + /.

https://github.com/quarto-dev/quarto/blob/227af7814a1e42737383ed4ce361242c36504dad/packages/editor/src/behaviors/omni_insert/omni_insert.ts#L71

With an AZERTY keyboard layout, there is no direct / key; instead, a / is inserted using Shift + :. Unfortunately, the addition of shift means that the aforementioned keybinding no longer fires.

As for potential resolutions; perhaps this command could also accept Ctrl + / as a keybinding on macOS? Or even, Mod + :?

It seems like Cmd + Shift + / will drive focus to the applications Help menu, and as far as I can see, this is handled by the OS and cannot be overridden. (Maybe there's something in the OS's registered keyboard shortcuts? I couldn't find it, though.)

Start in packages/editor/src/behaviors/omni_insert/omni_insert.ts around line 71 and reproduce the inline “Insert Anything” shortcut with an AZERTY layout on macOS. Compare possible alternate bindings while avoiding the system Help-menu shortcut; done means omni-completion can be triggered inline with the affected layout.