3 Ideas for web refactor:

• VS Code style - each folder has a 'common', 'browser', and a 'node' folder. Subfolders can have them too.
• Extension - each file indicates whether or not it's browser/node/both with extensions like '.node.ts', '.web.ts' and '.ts'
• Root folders - we have root folders that are 'common', 'browser', and 'node'. Other folders are mirrored in these subfolders