Implement Tracing in stacks-devnet-api

Add tracing capabilities which implement the [otel protocol](https://opentelemetry.io/docs/specs/otel/protocol/). We can start with auto-instrumentation to generate traces and spans for all network requests, and add custom instrumentation later to generate more in-depth spans for function calls if desired.

[The OpenTelemetry Rust library can be used for this.](https://github.com/open-telemetry/opentelemetry-rust)