docs: stub bulk of missing extension docs

docs/latest/extensions/modules/panel.md

@@ -1,3 +1,34 @@
 # Module: Panel
 
 ...
+
+```js
+import MyComponent from './MyComponent.js';
+
+export default {
+  id: 'example-panel-module',
+
+  /**
+   * @param {object} params
+   * @param {object} params.servicesManager
+   */
+  getPanelModule({ servicesManager }) {
+    return {
+      menuOptions: [
+        {
+          icon: 'list',
+          label: 'Magic',
+          target: 'target-component-id',
+        },
+      ],
+      components: [
+        {
+          id: 'target-component-id',
+          component: MyComponent,
+        },
+      ],
+      defaultContext: ['VIEWER'],
+    };
+  },
+};
+```