Function quote_zipper_fee 

pub async fn quote_zipper_fee(
    chain_id: u16,
    z_token: &str,
    zipper_endpoint: &str,
    environment: Option<&PolyesterChainEnvironment>,
    rpc: Option<&JsonRpcClient>,
) -> Result<ZipperFeeQuote>

Quote Zipper network fee via feeFactory.getFee(uint16,address).

Use the returned fee (or a small buffer above it) as max_fee for crate::chain::encode_funding_withdraw_to_chain.