#796 GET /workflows/<id> returns 500 for paused (and orphaned) runs - response enum missing statuses

spectree response validation: WorkflowStatus enum in api/openapi/models/{workflows,common}.py lacked 'paused' and 'orphaned' although the DB CHECK constraint allows both (migrations 01KD9RQB/01KD9SKA). Any GET /workflows/<id> of a paused/orphaned run 500'd. Found by the new pause_actually_pauses harness case. Fixed: added PAUSED + ORPHANED to both enums.