fix(cockpit): Update grafana-authentication-with-iam.mdx (#5776)

Author: sfinet-scw

pages/cockpit/reference-content/grafana-authentication-with-iam.mdx

@@ -47,13 +47,13 @@ From **November 3rd**, you will be able to choose from two authentication method
 
 ### New login method
 
-From **November 3rd**, you will be able to log in using your Scaleway credentials via the Scaleway console or saved links.
+From **November 3rd**, you will be able to log in using your Scaleway credentials. When accessing Cockpit Grafana via the Scaleway console or a saved link, you will be redirected to Scaleway's account page to authenticate. If already authenticated, you will be automatically logged in Grafana without taking any further action.
 
 ### New dashboard URLs
 
 To support both login methods during the transition, Grafana dashboards will have a **new URL**:
 
-- **Old URL:**
+- **Old URL (authentication via old Grafana users):**
   `https://<project_id>.dashboard.obs.fr-par.scw.cloud`
 
 - **New URL (IAM-authenticated):**
@@ -66,7 +66,7 @@ Both links will be functional until **January 20th, 2026**, after which only the
 
 Users must:
 
-- Be **Members** of your Scaleway Organization
+- Be **Owners** or **Members** of your Scaleway Organization
 - Have access to the Scaleway Project where the Cockpit is located
 - Have been granted either the `ObservabilityReadOnly`, the `AllProductsFullAccess`, or the `ObservabilityFullAccess` IAM permission set
 
@@ -84,7 +84,7 @@ You can manage Members and permission sets in the [IAM section of the Scaleway c
 Access to Grafana using the Scaleway console remains the same as before.
 
 1. Click **Cockpit** in the **Monitoring** section of the [console](https://console.scaleway.com/) side menu. The **Cockpit** overview page displays.
-2. Click **Open dashboards** to open your preconfigured dashboards in Grafana. You will be automatically logged in using your Scaleway account.
+2. Click **Access Grafana** to open your preconfigured or custom dashboards in Grafana. You will be automatically logged in using your Scaleway account.
 
 ### From a saved/shared link