spec: revamp LP APY calculation

[wakamex]

goals:

1. show fees earned from longer time-period of trading volume (30-day? since inception?)
2. be forward-looking and simpler, avoiding historical artifacts
3. avoid impact of temporary low-liquidity edge cases (-99% LP share price)
4. show dynamic impact of your decision to LP on the add liquidity screen

possible mechanisms:
for fees:

• collect fees earned from events, divide them out by LP amount at the time, add them up, turn into APR
  forward-looking:
• add up: latest yield source APY + fee APR
• (optionally?) include impact of open positions (weighted average long/short like in lp share price calculation)
  avoid low-liquidity edge cases:
• calculate everything with a simulated +$50k in liquidity (impact of closing positions, as in above)
  show dynamic impact on LP:
• add functionality to simulate LP APY with shocked liquidity to the sdk, call that function

[wakamex]

interestingly, defillama gives this guidance for fee-based yield:

Fee based APY values should be calculated over a 24h window

found at https://github.com/DefiLlama/yield-server/

[wakamex]

it would be nice to avoid -100% LP APY result