[Docker Desktop] Add settings for Docker Scout cache management

[mmarinchenko]

Tell us about your request

Potentially useful settings:

• The path to the Docker Scout cache (one may want to use a relatively small partition on a high-speed SSD or RAM disk for performance reasons)
• Maximum cache size to limit disk usage

Which service(s) is this request for?

Docker Desktop, Docker Scout.

Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?

Docker Scout saves image archives in the %TEMP%\docker-scout directory (on Windows) and never deletes them. This can quickly lead to 100+ GB of wasted disk space during active development. We need a way to manage this behavior.

Are you currently working around the issue?

• Windows Disk Cleanup tool can be automated to periodically clean the entire %TEMP% directory.
  OR
• A custom script can be scheduled manually for periodic cleaning of the %TEMP%\docker-scout directory.

Additional context

docker/for-win#244 (comment)

[jonnyrobots]

The docker scout command-line tool (included with Docker Desktop) provides clean up commands. Read more about the docker scout cache df and docker scout cache prune commands in our reference documentation here.

[mmarinchenko]

The OS shell also provides cleanup commands. But the docker scout command-line tool does not rely on this fact. I.e., it does not force the user to go and clean up after himself manually by running OS commands.

DD should provide the same level of responsibility. If it runs something under the hood that leads to pollution of the user's file system, it should provide the ability to manage this behavior at the same level of user interaction (i.e., the UI). Be it docker scout or anything else.