docs(kube play): clarify --annotation flag only affects containers, not pods

Update documentation and help text to clarify that the --annotation flag for podman kube play only adds Podman-specific annotations to containers in the created pods, not to the Kubernetes Pod object. Also note that the infra container does not receive the annotation. This addresses confusion reported in #26448 and related discussions.

Signed-off-by: shiavm006 <[email protected]>

Author: shiavm006

cmd/podman/kube/play.go

@@ -104,7 +104,7 @@ func playFlags(cmd *cobra.Command) {
 	flags.StringArrayVar(
 		&playOptions.annotations,
 		annotationFlagName, []string{},
-		"Add annotations to pods (key=value)",
+		"Add Podman-specific annotations to containers and pods created by Podman (key=value)",
 	)
 	_ = cmd.RegisterFlagCompletionFunc(annotationFlagName, completion.AutocompleteNone)
 	credsFlagName := "creds"

docs/source/markdown/options/annotation.container.md

@@ -5,3 +5,5 @@
 #### **--annotation**=*key=value*
 
 Add an annotation to the container<<| or pod>>. This option can be set multiple times.
+
+For `podman kube play`, this adds Podman-specific annotations to the containers and pods created by Podman, not to the Kubernetes YAML itself. These annotations can be used to configure Podman-specific features like user namespaces, volumes-from, and other container behaviors.

docs/source/markdown/podman-kube-play.1.md.in

@@ -201,6 +201,8 @@ An image can be automatically mounted into a container if the annotation `io.pod
 
 @@option annotation.container
 
+Note: For `podman kube play`, the `--annotation` flag adds Podman-specific annotations to the containers and pods created by Podman, not to the Kubernetes YAML itself. These annotations can be used to configure Podman-specific features like user namespaces (`io.podman.annotations.userns`), volumes-from (`io.podman.annotations.volumes-from`), and other container behaviors.
+
 @@option authfile
 
 #### **--build**