[ADD] LP Position calculation reference implementation

LP Position calculation Reference Implementation

Context

Currently LPers use various ecosystem apps to check their LP position returns (redeemable asset/rune, earnings, fees etc.)

Calculating an LP'ers position is non-trivial. Providing a reference implementation using the midgard endpoints for the broader ecosystem will improve LPer quality-of-life and boost confidence while mitigating the duplicate work necessary for each ecosystem project.

Desired Outcome

A JS implementation to calculate LP positions by pool:

Input:

• thor address

Output:

• Liquidity Added - Asset, Rune
• Liquidity Withdrawn - Asset, Rune
• Redeemable - Asset, Rune
• Earnings - Asset, Rune
• Gain/Loss - Asset, Rune
• current price of asset, rune in USD
• price of asset, rune when Liquidity was added in USD (caveat: some complexity with multiple deposits.)

Out of scope

Historic LP position over time - will be a follow on feature.

Validation

To validate the implementation a raw sql query can be used: https://gitlab.com/thorchain/midgard/-/blob/feature-queries-leifthelucky/internal/db/queries/members_with_details.sql