E1.2.1 Replace the module global with a ContextVar #29

Part of: T3 approval is process-wide state (not safe for concurrent or embedded use) (E1.2).

Task

Replace the module global with a ContextVar

Subtasks

• Set/reset with a token in main()
• Update every reader (check_owner, art_status, footer_status, doctor, topics, org)

Definition of done

• Tests added or updated and CI green
• Docs updated when the command surface or output changes
• No private registry data, local paths or private repository names in fixtures or docs