Add comprehensive AI agent instruction files for development guidance

[Copilot]

This PR adds a comprehensive set of instruction files to guide various AI agents and tools when working on the OnchainTestKit project. These files provide context-specific guidance for blockchain testing, wallet automation, and the unique challenges of browser extension testing.

Files Added

Core Agent Instructions

• .github/copilot-instructions.md - GitHub Copilot-specific guidance covering project architecture, development patterns, and code style conventions
• AGENTS.md - General agent instructions with project overview, key components, and common development workflows
• CLAUDE.md - Claude-specific instructions emphasizing analytical problem-solving and blockchain testing complexities
• GEMINI.md - Gemini-specific instructions focusing on optimization strategies and technical excellence

Specialized Development Guides

• .github/instructions/wallet-development.instructions.md - Comprehensive guide for wallet integration patterns, action types, and extension management
• .github/instructions/testing-framework.instructions.md - Testing framework usage, configuration patterns, and best practices
• .github/instructions/node-management.instructions.md - Local blockchain node management, fork mode configuration, and performance optimization
• .github/instructions/api-development.instructions.md - API design principles, extension points, and security considerations

Key Features

Each instruction file is tailored to its specific audience and includes:

• Project-specific context about blockchain testing challenges and wallet automation
• Practical code examples using the actual OnchainTestKit patterns and APIs
• Architecture guidance covering the modular wallet system, configuration builder, and test framework
• Best practices for handling asynchronous blockchain operations, browser extension automation, and network management
• Troubleshooting guides for common issues in blockchain testing environments

Technical Coverage

The instructions cover critical aspects of the OnchainTestKit ecosystem:

• Multi-wallet support - MetaMask, Coinbase Wallet, and Phantom integration patterns
• Fork mode testing - Advanced blockchain state forking for realistic test scenarios
• Browser automation - Complex extension popup handling and context management
• Network management - Multi-network testing and RPC provider optimization
• Type safety - Comprehensive TypeScript patterns for blockchain-specific types

These instruction files will help AI agents understand the unique challenges of blockchain application testing and provide more targeted, effective assistance when working on the OnchainTestKit codebase.

Fixes #32.

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

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[joe10832]

@copilot

[joe10832]

@copilot