async fn get_extended_params(&self, client: &Client) -> anyhow::Result<Vec<u8>> {
        let era = 0u8; // immortal era
        let tip = 0u128; // no tip
        let nonce = self.fetch_account_nonce(client).await?;

        // Encode the params
        let mut bytes = vec![era];
        Compact(nonce).encode_to(&mut bytes);
        Compact(tip).encode_to(&mut bytes);
        Compact(self.app_id).encode_to(&mut bytes);

        Ok(bytes)
    }
Returns a Compact-encoded extended extrinsic parameters
Extrinsic params used here:
- CheckMortality<AvailConfig>
- CheckNonce
- ChargeTransactionPayment
- CheckAppId
core/node/da_clients/src/avail/sdk.rs