Configure Copilot instructions per best practices

[Copilot]

Enhanced .github/copilot-instructions.md to align with GitHub's recommended structure for Copilot coding agents.

Added sections:

• About This Project - Project description, repository links, version
• Technology Stack - TypeScript, Node.js 20.x, Jest, OpenCV 4.12.0 WASM
• Table of Contents - Navigation links to all sections
• Security Considerations - WASM binary safety, memory management, dependency security, input validation
• External Documentation - OpenCV.js docs, live demos, TypeScript/Jest resources
• Contributing Guidelines - Workflow for changes, testing, and code review

File changes:

• 178 → 283 lines (+59%)
• 10 → 15 main sections
• All existing content preserved

Improves discoverability and provides security/contribution guidance while maintaining comprehensive development instructions.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• gh.io
  • Triggering command: curl -s REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>✨ Set up Copilot instructions</issue_title>
<issue_description>Configure instructions for this repository as documented in Best practices for Copilot coding agent in your repository.

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes ✨ Set up Copilot instructions #98

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