feat: integrate Sentry to BFF

- Added Sentry for error tracking in server.js and configured it with DSN from environment variables.
- Set up Sentry error handler for Fastify.
- Enhanced authentication logging in auth-utils.js by adding breadcrumbs for successful user authentication.
- Added Sentry breadcrumbs in http-proxy.js to track token refresh attempts and usage of crate.
- Updated package.json to include Sentry dependencies.

Author: n3rdc4ptn