Add a Math Library for Combining Pyth Prices on Solidity

[nirala-mehul]

This PR adds the Price Library, a Solidity library comibing prices using Price data types. The library includes functions for basic arithmetic operations, normalization, scaling, and fraction calculations on Price structs.

Changes Made

• Price Library: Added a new Solidity library (PriceLibrary.sol) that provides essential operations for manipulating Pyth prices.
• Forge Test Project: Introduced a test project (forge-test) to validate the functionality of the Price Library across various scenarios.
• Test Cases: Included comprehensive test cases within the forge-test project to ensure robustness and accuracy of the implemented functions.

Summary of Public Functions Implemented in Price Library

• getPriceInQuote: Calculates the price of a base asset in terms of a quote asset using division and scaling.
• getCollateralValuationPrice: Computes an adjusted price based on deposits, applying rate discounts linearly interpolated between initial and final rates.
• getBorrowValuationPrice: Computes an adjusted price based on borrows, applying rate premiums linearly interpolated between initial and final premiums.
• affineCombination: Performs an affine combination of two prices at a query point, useful for interpolation.
• normalize: Normalizes a Price struct by adjusting its price and confidence based on its exponent.
• scaleToExponent: Scales a Price struct to a target exponent, adjusting its price and confidence accordingly.
• div: Performs division between two Price structs, adjusting for precision and handling overflow conditions.
• add: Adds two Price structs together, ensuring their exponents match.
• cmul: Performs constant multiplication of a Price struct by a scalar constant.
• mul: Multiplies two Price structs together, adjusting their exponents and handling overflow.

Testing
Added a forge project and tests for PriceLibrary.

[vercel]

@nirala-mehul is attempting to deploy a commit to the pyth-web Team on Vercel.

A member of the Team first needs to authorize it.

[anihamde]

ditto

[ali-bahjati]

We have decided to move forward with #1746