Implement swipe-to-open/close gestures for Side Navigation

[jonboiser]

Summary

1. Uses https://vueuse.org/core/useswipe/#useswipe to listen to TouchEvents (so this should only work on touch screens, and not with mice) and open/close the SideNav when swiping right/left.

Screenshot from iOS simulator

(this can also be reproduced using Chrome mobile device simulator)

References

Fixes #6899

Reviewer guidance

The options for useSwipe, like the threshold, as well as the size of the "swipe zone" for opening the menu may need to be tuned. Do you have any suggestions?

I also made a decision not to place a guard around the swipe-left-to-close gesture for large devices. This means that something like a MS Surface user could use the gesture.

Also, this does not account for RTL languages (might need have a follow up issue). The isRTL prop should be accessible using https://v3.vuejs.org/api/composition-api.html#getcurrentinstance within the setup() function like this

const isRTL = getCurrentInstance().proxy.isRtl

In an RTL layout, the swipe directions need to be reversed, and the swipe zone on CoreBase needs to be moved to the right edge of the screen.

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Testing checklist

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Reviewer checklist

• Automated test coverage is satisfactory
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• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
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[rtibbles]

Seems like we'd need to address the RTL aspects before merging this.

[marcellamaki]

Closing out and updating the original issue to refer to this this as a starting point.