cuelang.org: support getting canonical URL for a page

[myitcv]

trafficstars

What page were you looking at?

https://alpha.cuelang.org/

What version of the site were you looking at?

https://github.com/cue-lang/cuelang.org/commit/eb2ecd699e4451e0284f62764d145abdd14040e2

What did you do?

Tried to toggle a canonical URL for the page.

What did you expect?

The URL to change from https://alpha.cuelang.org/ to something including the commit that generated the site, e.g. https://alpha-eb2ecd699e4451e0284f62764d145abdd14040e2-cue.netlify.app/

What did you see instead?

No option to do this.

Not a high priority one, but will perhaps be useful if we can support this out of the box using Netlify. The "Report an issue" link would then use this canonical URL.

Option too for adding a keyboard shortcut to do this, a la pkg.go.dev:

(that popup itself shows when ? is pressed)

[jpluscplusm]

The Netlify docs say that DEPLOY_URL is available during builds, and is the pathless URL permalink for this specific deployment: https://docs.netlify.com/configure-builds/environment-variables/#deploy-urls-and-metadata. An example is the redacted hxxps://6602c79f318a920008c4f2cc--cue.netlify.app/