GitLab hosted Codesandbox

Codesandbox can be self hosted quite easily by hosting the static sandpack script on a custom domain. It interacts directly with the https://unpkg.com/ CDN, removing the previous requirement of also operating a packager.

GitLab currently defaults to the Codesandbox.io domain. We should use a GitLab domain (e.g. gitlab-sandbox.com) and enable the feature by default for self hosted instances.

Proposal

Serve the javascript from an S3 bucket and skip needing to build https://gitlab.com/gitlab-org/gitlab-ce/issues/53060

We should fingerprint the javascript file so that it can be cached forever, and GitLab versions can link against specific versions of Codesandbox.

Remove the configuration option and enable Codesandbox by default for all instances of GitLab.

Update documentation to reflect that Codesandbox requires an internet connection to reach the new domain that we have purchased.

Links / references

https://docs.gitlab.com/ee/user/project/web_ide/index.html#enabling-client-side-evaluation