As a dev user, I need to calculate optimal proportion for stableswap deposits

[just-a-node]

Problem

Since users can deposit any arbitrary amounts via addLiquidity, UIs should be able to use the sdk to determine what the current optimal proportion is for token pairs in a pool.

This will allow for adding tokens in a balanced proportion (if a user has both sides available) OR supply any amounts and conduct a swap-then-deposit into the balanced proportion.

Ideas to solve this

Add a function that swaps any imbalanced amounts into the optimal proportion taking into account:

1. the slippage from the swap
2. the pool's altered reserve ratio due to the swap

Acceptance Criteria

• [ ] takes input amounts[] and calculates the optimal proportion to deposit given current pool ratio + slippage from an internal swap if input amounts are imbalanced + new pool ratio
• [ ] calls addLiquidity with new balanced amounts[]

Other

[alexwhte]

Please add your planning poker estimate with Zenhub @rhlsthrm

[alexwhte]

Confirm if we should remove from Alpha

[alexwhte]

@just-a-node evaluate getvirtual price vs optimal solution please

[just-a-node]

This can be calculated using calculateTokenAmount on the user's input for tokenX and tokenY.