Create Quick Start view with a walkthrough

[RandomFractals]

for onboarding devs and devops using k8s, gitops, or related command line tools.

Walkthrough steps might include:

• short gitops intro
• links to CLI tools
• list of gitops commands ...

see docs: https://code.visualstudio.com/updates/v1_57#_new-getting-started-experience

background info on welcome pages: https://github.com/microsoft/vscode/issues/63152

and walkthroughs: https://github.com/microsoft/vscode/issues/119097

[usernamehw]

https://code.visualstudio.com/api/references/contribution-points#contributes.walkthroughs

https://github.com/microsoft/vscode-extension-samples/tree/main/getting-started-sample