Prom client

[dantheuber]

• integrate prom-client for Prometheus metrics
• provide example http server utilizing pokeapi.co for a third party dependency
• added integration tests
• update readme to be more concise and remove emojis

[Copilot]

Pull Request Overview

This PR integrates Prometheus metrics collection using prom-client library, adds comprehensive testing infrastructure, and provides a practical example server. The main enhancement allows dependency monitoring with standardized Prometheus metrics while maintaining backward compatibility.

• Replaced custom Prometheus format with industry-standard prom-client library
• Added integration testing with mock server and real HTTP dependencies
• Created example server demonstrating PokeAPI monitoring with metrics endpoint

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
test/monitor.test.ts	Added unit tests for prom-client integration and registry management
test/integration/mock-server.ts	New mock HTTP server for integration testing
test/integration/mock-server.integration.test.ts	Integration tests using mock server with DependencyMonitor
src/types/dependency-monitor-options.ts	Added registry and collectDefaultMetrics options
src/types/dependency-monitor-interface.ts	Added getPrometheusRegistry method to interface
src/monitor.ts	Major refactor to use prom-client instead of custom metrics formatting
package.json	Added prom-client dependency and version bump
example/server.js	Complete example HTTP server with PokeAPI monitoring
example/README.md	Documentation for the example server
README.md	Updated documentation to reflect new features and simplified structure

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}