docs(k8s): add warning about additional costs when using easy deploy applications (#5552)

Author: bene2k1

pages/kubernetes/how-to/enable-easy-deploy.mdx

@@ -32,6 +32,8 @@ You can also deploy off-the-shelf applications pre-configured for Scaleway produ
 
 ## How to deploy an application
 
+### Deployment from Scaleway Container Registry
+
 <Message type="note">
   To deploy a container from an image stored within Container Registry, you must be logged in to the [Scaleway console](https://console.scaleway.com/).
 </Message>
@@ -86,7 +88,18 @@ You can also deploy off-the-shelf applications pre-configured for Scaleway produ
     *  Click **Deploy application** to proceed. The list of your deployed applications displays.
 
 
-  * **Deployment from Application Library**
+### Deployment from Application Library
+
+<Message type="important">
+  Depending on the application and the configuration you choose, additional charges may apply. These can include, but are not limited to:
+
+  - Block Storage (e.g., persistent volumes)
+  - Load Balancers (for managing traffic across applications)
+  - Logging services (e.g., Promtail to Cockpit log forwarding billed as [external data source](/cockpit/how-to/create-external-data-sources/))
+  - Other application-specific resources that generate costs
+
+  We recommend reviewing the documentation for each application and checking your resource usage regularly, using the [Cost Manager in the console](https://console.scaleway.com/billing/consumption) to understand any associated costs.
+</Message>
 
     * After selecting **Application Library**, enter a name for your container as well as the Kubernetes namespace on which the deployment will run. By default, the application is deployed on the `default` namespace.