If we go in that direction, I think we should also add types to node and app tsconfigs so that node types don't pollute default client code.
It also avoid the need for a vite-env.d.ts which IMO it's cleaner and what I do in my projects

Setting that has a different semantic to a separate file: https://www.typescriptlang.org/tsconfig/#types, so I'm not really sure if we should change that

Yeah I know it's different, but that the goal: you don't want to have process.env be ok for TS in the app files.

you don't want to have process.env be ok for TS in the app files.

We do use a lot of process.env in our frontend code, particularly process.env.NODE_ENV == "development" to switch to a dev rest api url.

Vite also allows process.env in app files https://vite.dev/guide/env-and-mode#node-env-and-modes

While this is supported for compatibility with the ecosystem, Vite way of doing this is import.meta.DEV which avoid using a Node concept inside a code that will run in browser