Add a share button to paste view

[supakeen]

It'd be useful to have a well visible share button on the paste views. This could copy the URL to clipboard or use navigator.share() (or both?).

[Robin5605]

Can I work on this?

[supakeen]

@Robin5605 Sure, I'll assign it to you :)

[supakeen]

Also from external discussion on the Python Discord let's not use navigator.share. Copying the URL to clipboard is fine though.

[Robin5605]

Cool, thanks!