Add spans to CRI runtime service and related client methods

This adds otel spans to CRI service mainly targeting mutating apis which includes:
* Sandbox apis - RunPodSandbox, StopPodSandbox, RemovePodSandbox
* Container apis - CreateContainer, StartContainer, StopContainer, RemoveContainer
* Attach, Exec and Exec Sync
* Containerd client methods: container.go, client.go, process.go and task.go

Signed-off-by: Swagat Bora <sbora@amazon.com>

internal/cri/server/sandbox_run.go

@@ -39,6 +39,7 @@ import (
 	sandboxstore "github.com/containerd/containerd/v2/internal/cri/store/sandbox"
 	"github.com/containerd/containerd/v2/internal/cri/util"
 	"github.com/containerd/containerd/v2/pkg/netns"
+	"github.com/containerd/containerd/v2/pkg/tracing"
 )
 
 func init() {
@@ -49,6 +50,7 @@ func init() {
 // RunPodSandbox creates and starts a pod-level sandbox. Runtimes should ensure
 // the sandbox is in ready state.
 func (c *criService) RunPodSandbox(ctx context.Context, r *runtime.RunPodSandboxRequest) (_ *runtime.RunPodSandboxResponse, retErr error) {
+	span := tracing.SpanFromContext(ctx)
 	config := r.GetConfig()
 	log.G(ctx).Debugf("Sandbox config %+v", config)
 
@@ -59,6 +61,11 @@ func (c *criService) RunPodSandbox(ctx context.Context, r *runtime.RunPodSandbox
 		return nil, errors.New("sandbox config must include metadata")
 	}
 	name := makeSandboxName(metadata)
+
+	span.SetAttributes(
+		tracing.Attribute("sandbox.id", id),
+		tracing.Attribute("sandbox.name", name),
+	)
 	log.G(ctx).WithField("podsandboxid", id).Debugf("generated id for sandbox name %q", name)
 
 	// cleanupErr records the last error returned by the critical cleanup operations in deferred functions,
@@ -172,6 +179,7 @@ func (c *criService) RunPodSandbox(ctx context.Context, r *runtime.RunPodSandbox
 		//
 		// To simplify this, in the future, we should just remove this case (podNetwork &&
 		// !userNsEnabled) and just keep the other case (podNetwork && userNsEnabled).
+		span.AddEvent("setup pod network")
 		netStart := time.Now()
 		// If it is not in host network namespace then create a namespace and set the sandbox
 		// handle. NetNSPath in sandbox metadata and NetNS is non empty only for non host network
@@ -356,6 +364,10 @@ func (c *criService) RunPodSandbox(ctx context.Context, r *runtime.RunPodSandbox
 			return nil, fmt.Errorf("failed to setup network for sandbox %q: %w", id, err)
 		}
 		sandboxCreateNetworkTimer.UpdateSince(netStart)
+
+		span.AddEvent("finished pod network setup",
+			tracing.Attribute("pod.network.setup.duration", time.Since(netStart).String()),
+		)
 	}
 
 	// TODO: get rid of this. sandbox object should no longer have Container field.