[Epic] Keyboard-based navigation

[curran]

As a user editing code with VZCode, I want to be able to do as many things as possible without leaving the keyboard, so that my work can be more efficient (and silent).

Current behavior: one can't even tab through the files in the sidebar.

Desired behavior: one should be able to navigate between files and tabs using only the keyboard.

Subtasks:

• Understand Existing keyboard shortcuts (and document if needed, related to #228 )
• Map out the additional keyboard shortcuts that we would want for this sort of accessibility
• Identify any third party libraries that may help us achieve this goal (such as React-ARIA)
• Make it possible to navigate up and down the sidebar using the keyboard
• Make it possible to open a file using the keyboard
• Make it possible to navigate through tabs using the keyboard
• Make it possible to navigate between the sidebar and the tabs
• Identify additional keyboard navigation required, such as for the icon buttons

[curran]

https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA

[curran]

Next step: try making the sidebar entries navigable with keyboard

Either using react-aria, or directly using the ARIA DOM API.

[curran]

Specific shortcut ideas:

• CTRL+1 to focus the open file
• Alt+0 and Alt+1 as alternatives to the Ctrl ones?

[curran]

Current direction:

(these could as separate PRs)

• [ ] Focus the code editor when you hit Alt+2
• [ ] Make it possible to navigate the sidebar (probably using react-aria)

[curran]

There's a bit of research to be done in terms of "best practices" for the interactions. I'm not sure exactly what it should be, but probably some combination of "tab", arrows, spacebar, and enter. These from Spectrum tree view look good!

https://spectrum.adobe.com/page/tree-view/#Keyboard-interactions