[type-compiler] exclude declare statements

[marcj]

e.g. https://github.com/epicweb-dev/epic-stack/blob/e70fee5a087954b1818234443ebc49a87b5ca7d0/app/utils/env.server.ts#L60

type ENV = ReturnType<typeof getEnv>

declare global {
	var ENV: ENV
	interface Window {
		ENV: ENV
	}
}

should be avoided as we don't need them at all at runtime