feat: add autonomous-trading-agent-agentkit tutorial

[jadonamite]

Summary

Adds a comprehensive tutorial on building an Autonomous Trading Agent using Coinbase AgentKit, LangChain, and Node.js.

Content

• Stack: Node.js, TypeScript, LangChain, AgentKit (CDP).
• Network: Base Sepolia.
• Key Features:
  • Setup of CDP Server-Side MPC Wallet.
  • Configuration of cdpWalletActionProvider for token swaps.
  • Implementation of an autonomous while(true) loop for continuous agent operation.
  • Handling of faucet requests and gas management.

Motivation

AgentKit is a critical new tool for the Base ecosystem. This guide provides a "Hello World" for DeFi agents, moving beyond simple chatbots to actual autonomous onchain interaction.

Type of Change

• New Tutorial/Guide
• Update to existing guide
• Bug fix

Verification

• Tested locally on Base Sepolia.
• Verified faucet funding works.
• Verified swap actions execute successfully.

[cb-heimdall]

🟡 Heimdall Review Status

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