Explore allowing custom doctor flags to check dependencies outside a project or in a custom project

[rober-m]

There could be a case where a user:

• Wants to check if they have a set of dependencies available independently of the ones used in their current project.
• Wants to check for dependencies of a specific tool outside a project.
• Renamed a folder (e.g., on-chain -> contracts) and the doctor doesn't detect the folder.

Do we care about those cases enough to do something about them?
How should we solve them (e.g., cardano-init doctor --onchain <FOLDER> or cardano-init doctor --tool <TOOL>)?