Support Nx standalone applications

Nx 15.3 introduced the concept of standalone applications. This is convenient if a user wants to avoid working with a monorepo-based setup and instead work with a single project for a single forge app.

The root project would be a Forge app project.

https://nx.dev/concepts/integrated-vs-package-based#standalone-applications
https://www.youtube.com/watch?v=qEaVzh-oBBc