feat: add SwapAPI skill for DEX-aggregated token swaps on 40+ evm networks

[MinoXBT]

Summary

Add SwapAPI skill to fetch executable token swap calldata with automatic DEX aggregation for best pricing across 40+ EVM chains. Zero fees.

What it does

• Smart Aggregation - Automatically routes through optimal DEXs (Uniswap, Curve, etc.) to find best prices
• Zero Fees - Free to use. No platform fees, no API fees, no hidden costs (standard network gas fees apply)
• One GET request returns ready-to-sign transaction data
• No API keys or authentication required
• 40+ chains supported: Ethereum, Base, Arbitrum, Polygon, Optimism, and more

Usage Example

curl "https://api.swapapi.dev/v1/swap/8453?\
tokenIn=0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE&\
tokenOut=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913&\
amount=1000000000000000&\
sender=0xYourAddress"
Returns:
{
  "success": true,
  "data": {
    "tx": {
      "to": "0x...",
      "data": "0x...",
      "value": "1000000000000000",
      "gas": "150000"
    },
    "swapPrice": 2435.12,
    "priceImpact": 0.0003
  }
}