DNUP will need a manifest that tracks installs that lives in the user local context. That manifest will need information about the install, such as whether it is reliant on a global.json file, is a standalone install to a custom directory, or is an install managed by 'dnup'. This will inform the update decisions that are made by the 'dnup update' command. It is important that the manifest includes the path and other information about the install.

This will need some design work but ultimately it will be easier to determine at implementation time and modify underneath the 0.x.y semantic versioning. We can keep breaking the manifest pattern until we actually release.

The manifest should be verified and not treated as a raw source of truth - users may delete something on the file system. We should cache global json info when possible to avoid multiple file lookups, as IO is expensive.