feat(cli): load quickstart catalogs using in-memory repository clone

[sachin9058]

Summary

Update the quickstart command to dynamically load rule and profile catalogs from a remote repository using an in-memory git clone.

Previously, the quickstart flow relied on embedded/static catalog data and installed a limited set of rules. This change enables loading catalogs directly from a repository at runtime, improving flexibility and aligning with the direction discussed in #6339.

The clone operation is performed inline using go-git with in-memory storage, avoiding filesystem side effects and keeping the CLI lightweight. If cloning or parsing fails, the existing embedded catalog flow is used as a fallback to preserve backward compatibility.

This addresses part of #6339 by enabling dynamic catalog loading from a repository.

Testing

• Ran:

  make lint-fix
  go test ./...

• Verified CLI behavior by running:
  go run ./cmd/cli quickstart
• Confirmed catalog loading works with a valid repository
• Verified fallback behavior when repository cloning fails (invalid repo URL)
• Ensured no regressions in existing quickstart functionality

[coveralls]

coverage: 59.539%. remained the same — sachin9058:feat/quickstart-inmemory-catalog-clean into mindersec:main