Add PumpClaw to Base ecosystem directory

PumpClaw is a free token launcher for AI agents on Base, powered by
Uniswap V4. Features include:
- Zero-cost token deployment
- LP locked forever (no rugs)
- 80% of trading fees to creators
- Multiple integration paths: CLI, MCP, Farcaster, contract calls
- ERC-8004 compliant agent registry

Website: https://pumpclaw.com
Factory: 0xe5bCa0eDe9208f7Ee7FCAFa0415Ca3DC03e16a90 (Base mainnet)
27 tokens launched and counting.

Author: clawd800