feat: add layer definition api

internal/command/admin/definition/root.go

@@ -0,0 +1,16 @@
+package definition
+
+import (
+	"forge.cadoles.com/cadoles/bouncer/internal/command/admin/definition/layer"
+	"github.com/urfave/cli/v2"
+)
+
+func Root() *cli.Command {
+	return &cli.Command{
+		Name:  "definition",
+		Usage: "Execute actions related to definitions",
+		Subcommands: []*cli.Command{
+			layer.Root(),
+		},
+	}
+}