feat: mention that the user can change the placement of the dev toolb…

…ar (#7720)

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>

src/content/docs/en/guides/dev-toolbar.mdx

@@ -34,7 +34,7 @@ The dev toolbar aims to provide a quick and easy way to catch common issues duri
 
 ### Settings
 
-The Settings app allows you to toggle different settings for the development toolbar, such as verbose logging, and the ability to disable notifications.
+The Settings app allows you to configure options for the development toolbar, such as verbose logging, disabling notifications, and adjusting its placement on your screen.
 
 ## Extending the dev toolbar
 

src/content/docs/en/reference/dev-toolbar-app-reference.mdx

@@ -144,6 +144,21 @@ This event is fired when the user clicks on the app icon in the Dev Toolbar.
   }
 ```
 
+### `placement-updated`
+
+This event is fired when the user changes the placement of the Dev Toolbar.
+
+```ts title="src/my-app.js" {4-6}
+  export default {
+    // ...
+    init(canvas, eventTarget) {
+      eventTarget.addEventListener('placement-updated', (event) => {
+        console.log(`Placement set to ${event.detail.placement}`);
+      })
+    }
+  }
+```
+
 #### `state: boolean`
 
 Indicates whether or not the app is enabled after the user's click.