Read an owned retained run and evidence

Requires API-key or first-party session authentication and a current account in the default-off server cohort. Valid current membership does not require a new paid subscription. Existing API quotas still apply. Responses are private, no-store. Unknown and repeated query parameters are rejected. This contract does not indicate source activation, deployment or an SDK release. Retained objects are scoped to the current account and their creator; no caller-supplied account/user grant is accepted. Current source rights are checked for every read/use, independently of archived grants. Withdrawn rights or changed source semantics may withhold a saved result; its immutable archived payload is not rewritten.