deprecate: mark data-imports command as deprecated

Mark the data-imports command and its subcommands as deprecated,
directing users to use Vitess workflows for imports instead.
Users will see a deprecation warning pointing to the documentation
at https://planetscale.com/docs/vitess/imports/database-imports

Author: cursoragent

internal/cmd/dataimports/dataimports.go

@@ -11,6 +11,7 @@ func DataImportsCmd(ch *cmdutil.Helper) *cobra.Command {
 		Use:               "data-imports <command>",
 		Short:             "Create, list, and delete branch data imports",
 		Long:              "Create, list, and delete branch data imports.\n\nThis command is only supported for Vitess databases.",
+		Deprecated:        "Vitess workflows are now available in the PlanetScale dashboard. See https://planetscale.com/docs/vitess/imports/database-imports for more information.",
 		PersistentPreRunE: cmdutil.CheckAuthentication(ch.Config),
 	}