add type hints

[devidw]

• Make sample data blocks in readme collapsable, add console link
• Add dev container configuration files
• Extend .gitignore
• Add some doc comments
• Add some type hints
• Fix Instance attribute attribute_name defined outside init by setting instance properties as None inside __init__

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I couldn't validate that all type hints are set correctly, but will definitely do so, as soon as my crown arrives. ✨