Add CI build pipeline with GitHub Actions

[Copilot]

This PR implements a comprehensive CI build pipeline to address issue requirements for building the code and running tests.

Changes Made

GitHub Actions Workflows

Added two complementary workflows to ensure robust CI/CD:

1. build.yml - Primary cross-platform build pipeline:

   • Tests on Ubuntu, Windows, and macOS
   • Matrix builds with Node.js 18.x and 20.x
   • Runs linting, type checking, compilation, and packaging
   • Verifies build outputs are created correctly
   • Uploads build artifacts for the latest Node.js version

2. ci.yml - Advanced workflow with extension testing:

   • Includes VS Code extension testing with xvfb display server
   • Creates VSIX packages on main branch pushes
   • Separate packaging job for release artifacts

Build Pipeline Steps

The CI pipeline executes the following quality gates:

• ESLint code linting
• TypeScript type checking
• Development compilation with esbuild
• Production packaging (minified)
• Test compilation
• VSIX package creation (for releases)

Configuration Fixes

• Fixed repository URL in package.json to enable proper VSIX packaging
• Both workflows trigger on pushes and PRs to main and develop branches

Documentation

Enhanced the README with a comprehensive Development section including:

• Build instructions and available npm scripts
• CI status badge integration
• Development workflow documentation
• Testing and packaging guidelines

Testing

All build steps have been validated locally:

• ✅ Linting passes with no errors
• ✅ Type checking completes successfully
• ✅ Compilation generates expected output files
• ✅ Production packaging creates minified bundles
• ✅ VSIX packaging works correctly

The pipeline ensures code quality and successful builds across multiple platforms before merging to main, providing confidence in the extension's reliability across different environments.

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:

• update.code.visualstudio.com
  • Triggering command: node /home/REDACTED/work/github-copilot-token-usage/github-copilot-token-usage/node_modules/.bin/vscode-test (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

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This section details on the original issue you should resolve

<issue_title>Add a CI build pipeline</issue_title>
<issue_description>Build the code and run the tests</issue_description>

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

Fixes #8

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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.

[rajbos]

LGTM