Pull Request: Add /metrics Endpoint with Request Tracking

[human-77]

Summary

This PR adds a Prometheus-compatible metrics endpoint to monitor server health and track HTTP requests by route and status code.

Changes

1. route.ts

Implements a /metrics endpoint that exposes server metrics in Prometheus format, including:

• Server uptime indicator (up)
• CPU usage (process_cpu_seconds_total)
• Memory metrics (RSS, heap total/used, external memory, array buffers)
• HTTP request counters grouped by route and status code (http_requests_by_status)

This endpoint can be scraped by Prometheus or other monitoring tools to track application performance and health.

2. requestCounter.ts

Provides a lightweight in-memory request counter utility with two main functions:

• incrementCounter(route, statusCode): Records each HTTP request with its route and status code
• getStatusCounters(): Retrieves the accumulated request statistics

Uses globalThis to persist counters across module hot-reloads in development, ensuring metrics aren't lost during the session.

3. metrics.test.ts

Adds a basic test suite for the metrics endpoint to ensure:

• The /metrics endpoint responds successfully
• The response returns valid string content in Prometheus format

Use Case

These changes enable observability for the MCP server, allowing developers and operators to:

• Monitor resource usage (CPU/memory)
• Track request patterns and error rates
• Set up alerts based on status code distributions
• Debug performance issues in production

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[human-77]

If it's not possible do the merge without signing the CLA I won't mind if you guys just clone my repo and add to the project. It's just three files.

Ignore this, the message didn't showed to me until I reload the page

[human-77]

I confirm that I have read and hereby agree to the OpenZeppelin Contributor License Agreement

[wwwmilan]

Any prediction on when will this be merged? My team needs observability.