Implements scripts/doctor.mjs with semver-aware path selection
(noop/update/upgrade/fresh_install/fix_oauth/fix_service) and the JSON
contract documented in the design spec.
Service health + OAuth checks integrated; mockable via opts.mockHealth
for unit tests. 8 unit tests cover the kind dispatch tree and the
next_action shape for each kind.
No cli.js citation needed: this is OCP-internal tooling with no
corresponding cli.js operation.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
