Enhance Copilot instructions with comprehensive development workflow guidance

[Copilot]

Configures .github/copilot-instructions.md per GitHub best practices for Copilot coding agent to improve autonomous issue resolution.

Changes

• Development Workflow: Added all npm scripts with usage (dev, build, test, lint, coverage, license checks)
• Testing Standards: Documented Vitest/Cypress patterns, 80% coverage target, complete test structure with imports
• Code Organization: File structure conventions, both .test.tsx and .test.ts support
• Security & Compliance: License requirements (MIT, Apache-2.0, BSD, ISC), security scanning expectations
• PR Guidelines: Review standards and merge requirements

Example Test Pattern

import { render, screen } from "@testing-library/react";
import { describe, it, expect } from "vitest";

describe("ComponentName", () => {
  it("should render correctly", () => {
    const props = { /* test props */ };
    render(<ComponentName {...props} />);
    expect(screen.getByText("expected text")).toBeInTheDocument();
  });
});

Expanded from 96 to 257 lines with actionable guidance for build, test, and security workflows.

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:

• download.cypress.io
  • Triggering command: node dist/index.js --exec install (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 #292

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.