feat: getPosition/usePosition

[luchobonatti]

🚀 Add getPosition and usePosition to retrieve individual Uniswap V4 positions

Summary

This PR adds two new utilities to simplify querying a single Uniswap V4 LP position:

• getPosition(tokenId, chainId?) – returns detailed on-chain data for a given position
• usePosition(tokenId, options?) – a React hook built on top of react-query for reactive usage

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✅ Features

• Fetches position metadata via:
  • getPoolAndPositionInfo
  • getPositionLiquidity
  • getSlot0
  • getLiquidity
• Constructs Token, Pool, and Position objects using the official Uniswap V4 SDK
• Returns:
  • token0 / token1 metadata
  • Amounts of each token in the position
  • Fee tier, tick spacing, current tick
  • Pool liquidity and slot0 data
  • Pool ID

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🧠 Why

Before:

• Manually call 3–4 contracts
• Decode ABI bytes manually
• Build Pool and Position instances yourself

After:

const position = await getPosition(tokenId)
// Or with the hook:
const { data, isLoading } = usePosition(tokenId)