Add utilities for preparing Conversion, Swap-to-pay, and Swap-to-conversion payment transactions

[MantisClone]

Problem

Builders have experienced difficulty integrating Conversion, Swap-to-pay, and Swap-to-conversion payments due to the lack of utilities or templates for preparing transactions.

Solution

Open source the utilities that Request Finance uses to prepare Conversion, Swap-to-pay, and Swap-to-Conversion payments.

Reference

• https://github.com/RequestNetwork/invoicing/blob/master/src/features/payment/utils/payment-settings/getConversionPaymentValues.ts
• https://github.com/RequestNetwork/invoicing/blob/master/src/features/payment/utils/payment-settings/getSwapPaymentValues.ts
• https://github.com/RequestNetwork/invoicing/blob/master/src/features/payment/utils/payment-settings/getSwapWithConversionPaymentValues.ts
• https://github.com/RequestNetwork/invoicing/blob/master/src/lib/conversion.tsx
• https://github.com/RequestNetwork/invoicing/blob/master/src/lib/chainlink.ts

Definition of Done

• Ask Request Finance for permission to open-source their utils - Private Slack Conversation - Approved ✅
• Copy the Request Finance utilities to the requestNetwork repo and make them easy to call.