enable use of stablecoins for vouches

Objective

allow people to vouch with stablecoins that hold value rather than a volatile asset like ethereum

Motivation & Purpose

to put things in perspective - ethereum was valued at ~4700 a week ago and as of today ~3800

while the inverse may also eventually be true, it would be an improvement to the ethos UX if users can utilize stablecoins for vouches, rather than a fluctuating asset

Specification

enable options to select major stablecoins such as usdt or usdc when user clicks on the vouch button

enable vouch rewards to be redeemed in stablecoins

Iterative Development

enable users to convert any ethereum in their current vouches into stablecoins at a time of their choosing and vice versa

this is at the end of the day deployable capital, locked up as vouches; rather than have people withdraw said capital, they can make a minimal yet profitable rebalance