POST /api/relationships/{edge_handle}/retype.{
"confidence": "tentative",
"correlation_id": "807686c4-116c-44b3-a01c-b14b50e31bcc",
"invocation_id": "9efe53a2-0f4e-415e-a218-b405e1367798",
"model": "string",
"persona": "string",
"rationale": "string",
"reasoning": "string",
"edge_kind": "express",
"polarity": "forward"
}