Improve build system

The current build system has a series of issues that should be resolved, in particular:

• Component bundles are rolled-up, meaning that component used by more than one wrapper component throw an error on import.
• The build config is spread throughout multiple build tools depending on the environment: Babel, Webpack, Jest, Storybook, etc.
• Components have to be declared individually in package.json (which is automated with a script, but still not ideal).

Ideally, we'll solve this by migrating to Vite; which should also serve to modernize the tooling in the repository. However, if it isn't possible (or seems like too much work), we should at least fix these with the current tooling.