Add instrumentation and tracing

[luksamuk]

Tracing is an important feature and is also a topic of great interest for this project.

It is also something nice that goes well with the stack proposed on #12.

Suggested stack:

• OpenTelemetry (tooling, libraries; use Jaeger integration)
• Grafana Tempo (trace aggregator)
• Grafana (dashboards)

Useful Links:

• Grafana Tempo/Get Started/Example setups