Getting started with the VS Code extension

[mikebarkmin]

It would be nice if we would have a welcome screen for the VS Code extension. Otherwise, a user does probably not know what to do with it. So we need to define a series of steps for implementing something similar to:

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

Possible steps could be:

• Create new Hyperbook aka. run command hyperbook.new
• Edit index.md in the folder book
• Create new page in the book folder
• Insert a snippet
• Change the frontmatter of the new page
• Done

Maybe we also should add steps about syncing the Hyperbook to a git remote and triggering the pipeline.

[mikebarkmin]

For other common operations like adding a logo, changing the brand color etc. we should create videos and add a guide to the documentation.