feat: add core liquidity management structs to LiquidityManagerV2

[SynnekOG]

Pull Request

Summary

This PR introduces foundational data structures to support advanced liquidity management in LiquidityManagerV2.

Changes

• Added LiquidityProvider struct
  • Tracks contributions, rewards, vesting status, and emergency withdrawal times.
• Added PoolInfo struct
  • Stores pool state, thresholds, vesting duration, creator, and provider mappings.
• Added LiquidityPosition struct
  • Represents active liquidity positions with token pair details, fee tier, tick range, liquidity amounts, and timestamps.

Motivation

These structs establish the backbone for:

• Managing individual liquidity providers and their states.
• Tracking pool-wide metrics, thresholds, and emergency controls.
• Representing positions in a standardized way compatible with AMM-style mechanics.

This prepares the contract for more complex features such as reward distribution, vesting enforcement, and multi-pool support.