feature request: ability to estimate fees from NetworkFacade class

[comountainclimber]

As a wallet developer using the slick NetworkFacade class it would be very helpful to add a method for calculating estimated fees for a transaction it would be amazing if API was similar to that of the transferToken method!

[lock9]

Hi @ixje , is this related to the smartCalculateFee?

[ixje]

it can be done with just smartCalculateNetworkFee but that would require manually building the tx. I believe @comountainclimber is basically asking for combining this

neon-js/packages/neon-api/src/NetworkFacade.ts

Lines 65 to 98 in 7eb101a

	const client = this.getRpcNode();
	const txBuilder = new TransactionBuilder();
	for (const intent of intents) {
	if (intent.decimalAmt) {
	const [tokenInfo] = await getTokenInfos([intent.contractHash], client);
	const amt = u.BigInteger.fromDecimal(
	intent.decimalAmt,
	tokenInfo.decimals
	);
	txBuilder.addNep17Transfer(
	intent.from,
	intent.to,
	intent.contractHash,
	amt
	);
	} else if (intent.integerAmt) {
	txBuilder.addNep17Transfer(
	intent.from,
	intent.to,
	intent.contractHash,
	intent.integerAmt
	);
	} else {
	throw new Error("no amount specified!");
	}
	}
	const txn = txBuilder.build();
	const validateResult = await this.validate(txn);
	if (!validateResult.valid) {
	throw new Error("Unable to validate transaction");
	}

with this

neon-js/packages/neon-api/src/api/calculateNetworkFee.ts

Line 72 in 7eb101a

export async function smartCalculateNetworkFee(

into a single function