Set up a monorepo with Git

Set up a monorepo for [Number] packages using [Turborepo / Nx / Lerna]. Define the workspace directory structure for applications and shared libraries. Configure shared dependency hoisting and the workspace protocol for inter-package references. Set up per-package build, test, and lint scripts that can be run individually or across the whole workspace. Define the build task dependency graph so packages build in the correct order. Configure CI to detect which packages are affected by a given change and only rebuild and retest those packages.