Pin package dependencies

[kajogo777]

We should be able to pin package dependencies, and support upgrades following the main branch.

This command should install packages from pinned commits only (or pinning them if they don't exist) devx project update

This command should upgrade the binned commit hashes to the latest commit or to a user-specified commit devx project upgrade

Ultimately we should design the packaging & schema convention to be immutable like Nix or Grafana Thema, so it's very hard to introduce breaking changes to configurations.