Enable tree shaking

[tarrencev]

It would be great if we could enable tree shaking of the starknet.js library for the next version.

[tabaktoni]

Tree shaking is enabled in the project, but it's only fully effective for your ESM (.mjs) builds.
When another project imports your library as an ES module (using a .mjs file), its bundler will be able to tree-shake any unused exports from the library, leading to a smaller final bundle size.
Is there something I'm missing?