curl --request POST \
  --url https://api.sumvin.com/v0/safe/rpc \
  --header 'Content-Type: application/json' \
  --data '
{
  "chain_id": 123,
  "user_operation": {},
  "entrypoint": "0x0000000071727De22E5E9d8BAf0edAc6f37da032"
}
'

{
  "_links": {
    "self": {
      "href": "<string>",
      "method": "GET",
      "templated": false,
      "description": "<string>"
    }
  },
  "user_op_hash": "<string>",
  "status": "submitted"
}