feat: Add Uniswap V4 liquidity management actions

[guglxni]

Summary

Add liquidity management actions to the Uniswap V4 action provider, enabling agents to mint, increase, decrease, and collect fees from V4 liquidity positions via the PositionManager contract.

Motivation

The current V4 provider (PR #951) only supports swaps and quotes. Liquidity provision is a core DeFi primitive and the PositionManager address is already stored in our constants. Adding LP management would make the V4 provider feature-complete.

Proposed Actions

Action	Description
add_v4_liquidity	Mint a new liquidity position with specified price range and amounts
increase_v4_liquidity	Add more liquidity to an existing position
decrease_v4_liquidity	Remove liquidity from an existing position
collect_v4_fees	Collect accumulated swap fees from a position
get_v4_position	Query details of an existing position (liquidity, fees owed, price range)

Implementation Notes

• Uses the PositionManager contract (already in constants)
• Positions are ERC721 NFTs (same as V3 but through new PositionManager)
• Need to handle tick math for price range specification
• Agent should help users select appropriate price ranges based on current pool price
• Support both native ETH and ERC20 token pairs

Dependencies

• Builds on the V4 action provider from PR feat: add Uniswap V4 action provider #951
• PositionManager ABIs needed (partially available in V4 periphery)

References

• Uniswap V4 PositionManager
• V4 Periphery Source

[guglxni]

I'd like to work on this. Could a maintainer please assign this to me?