[#12] tracing: Add tracing package

Add tracing config, implementation and setup

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/tracing/span.go

@@ -0,0 +1,12 @@
+package tracing
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/trace"
+)
+
+// StartSpanFromContext creates a span and a context.Context containing the newly-created span.
+func StartSpanFromContext(ctx context.Context, operationName string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	return tracer.Load().(*tracerHolder).Tracer.Start(ctx, operationName, opts...)
+}