feat(plan): add plan section support

internals/plan/export_test.go

@@ -0,0 +1,20 @@
+// Copyright (c) 2024 Canonical Ltd
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 3 as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package plan
+
+// ResetLayerExtensions resets the global state between tests.
+func ResetLayerExtensions() {
+	layerExtensions = map[string]LayerSectionExtension{}
+}