feature: open telemetry module

[jknack]

{
  // 1. Install the core engine FIRST
  install(new OtelModule(
    new OtelLogback(),       // Injects Trace IDs into application logs
    new OtelServerMetrics(), // Exports HTTP server metrics (e.g., Netty, Undertow, Jetty)
    new OtelHikari()         // Traces database connection pools
  ));

  // 2. Add the tracing filter to the routing pipeline
  use(new OtelHttpTracing());

  // 3. Define routes
  get("/books", ctx -> "List of books");
}