fix: Allow module-stage-list to have top-level keys be optional

src-tsp/main.tsp

@@ -145,6 +145,16 @@ model ImportedModule {
 @jsonSchema("module-stage-list-v1.json")
 @extension("additionalProperties", false)
 model ModuleStageList {
-  ...ModuleList;
-  ...StageList;
+  /**
+   * A list of [modules](https://blue-build.org/reference/module/) that is executed in order. Multiple of the same module can be included.
+   *
+   * Each item in this list should have at least a `type:` or be specified to be included from an external file in the `recipes/` directory with `from-file:`.
+   */
+  modules?: Array<ModuleEntry>;
+
+  /**
+   * A list of [stages](https://blue-build.org/reference/stages/) that are executed before the build of the final image.
+   * This is useful for compiling programs from source without polluting the final bootable image.
+   */
+  stages?: Array<StageEntry>;
 }