[#1714] lens: Add meta subcommand

Includes:
1. `inspect`
2. `list-garbage`
3. `list-graveyard`

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

cmd/neofs-lens/internal/meta/root.go

@@ -0,0 +1,30 @@
+package meta
+
+import (
+	"github.com/spf13/cobra"
+)
+
+var (
+	vAddress string
+	vPath    string
+)
+
+type epochState struct{}
+
+func (s epochState) CurrentEpoch() uint64 {
+	return 0
+}
+
+// Root contains `meta` command definition.
+var Root = &cobra.Command{
+	Use:   "meta",
+	Short: "Operations with a metabase",
+}
+
+func init() {
+	Root.AddCommand(
+		inspectCMD,
+		listGraveyardCMD,
+		listGarbageCMD,
+	)
+}