feat: Add getUserPositionInPool external view function for liquidity position introspection

[2PykeETH]

Summary

This PR introduces the getUserPositionInPool external view function to the TestAMMContract smart contract.
The function provides a structured and detailed overview of a user’s position within a specific prediction market pool — enabling enhanced frontend visibility, analytics integration, and on-chain composability for liquidity tracking.

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Changes

🧩 New Function — getUserPositionInPool(address _user, bytes32 _marketId)

Purpose:

To expose comprehensive position data for a given user and market pool without modifying contract state.

Function Signature:

function getUserPositionInPool(address _user, bytes32 _marketId)
    external
    view
    returns (
        address operator,
        address token0,
        address token1,
        uint24 fee,
        uint128 liquidity,
        int24 tickLower,
        int24 tickUpper,
        uint128 tokensOwed0,
        uint128 tokensOwed1,
        uint256 amount0,
        uint256 amount1
    );