Sandcastle dev deployment

[jjspace]

Description

Set up CI deployment of the new version of sandcastle to https://dev-sandcastle.cesium.com/. I set this to only run on the sandcastle-v2 branch which acts as the "base" feature branch for all of the Sandcastle rebuild. That said the vite configs and other changes rely on the updated logic in other open PRs like #12639 and #12631 so it can't be merged until they are.

I did run the CI job once on this branch and confirmed it does work and there's now a version of the new sandcastle at https://dev-sandcastle.cesium.com/

Issue number and link

Part of #12566

Testing plan

Make sure Sandcastle is on https://dev-sandcastle.cesium.com/

To test the prod build run npm run build-prod in the package directory
Then run npx http-server in the /Build/Sandcastle2 directory. This directory should contain copies of all files needed for Sandcastle and run in "isolation" if you copied it to another directory

Author checklist

• I have submitted a Contributor License Agreement
• I have added my name to CONTRIBUTORS.md
• I have updated CHANGES.md with a short summary of my change
• I have added or updated unit tests to ensure consistent code coverage
• I have updated the inline documentation, and included code examples where relevant
• I have performed a self-review of my code

[github-actions]

Thank you for the pull request, @jjspace!

✅ We can confirm we have a CLA on file for you.

[ggetz]

Looks like the vite build is bundling a copy of CesiumJS already. Is there a reason we are doing that and then pulling another copy of the latest version from github?

[jjspace]

Simply because it was in the prod deploy workflow I copied from. Confirmed it's not needed and removed 👍

[jjspace]

@ggetz I think this should be good to go now. In testing the last change I realized we had no way to tell what "version" of the code was running or when the server cache was updated. I added a very quick commit hash to the top right as a short term solution. We can figure out a better way to display the version later, todo added to the main list.

[ggetz]

Sounds good, thanks @jjspace!