Modified the resource-migration docs

docs/tutorials/resource-migration.md

@@ -232,4 +232,84 @@ nginx-svc    NodePort    10.13.161.255   <none>        80:30000/TCP   54s   app=
 ```
 
 As you see, you shall find `nginx` application related resource are all propagated to `member2` cluster, 
-which means the higher priority `PropagationPolicy` does work.
+which means the higher priority `PropagationPolicy` does work.
+
+---
+
+### Apply Higher Priority PropagationPolicy
+
+#### Step 5: Write the code
+
+Create a new file `/tmp/pp-for-nginx-app.yaml` and copy the text below into it:
+
+```yaml
+apiVersion: policy.karmada.io/v1alpha1
+kind: PropagationPolicy
+metadata:
+  name: nginx-pp
+spec:
+  conflictResolution: Overwrite
+  placement:
+    clusterAffinity:
+      clusterNames:
+      - member1
+      - member2                   ## propagate to more clusters other than member1
+  priority: 10                    ## priority greater than above PropagationPolicy (10 > 0)
+  preemption: Always              ## preemption should equal to Always
+  resourceSelectors:
+  - apiVersion: apps/v1
+    kind: Deployment
+    name: nginx-deploy
+  - apiVersion: v1
+    kind: Service
+    name: nginx-svc
+  schedulerName: default-scheduler
+```
+
+#### Step 6: Run the command
+
+Apply this higher priority `PropagationPolicy` to the Karmada control plane:
+
+```shell
+kubectl --context karmada-apiserver apply -f /tmp/pp-for-nginx-app.yaml
+propagationpolicy.policy.karmada.io/nginx-pp created
+```
+
+#### Step 7: Verification
+
+```shell
+kubectl --context member1 get deploy -o wide
+kubectl --context member1 get svc -o wide
+kubectl --context member2 get deploy -o wide
+kubectl --context member2 get svc -o wide
+```
+
+You should see the `nginx` application related resources originally in `member1` also propagated to `member2`, completing the migration of resources :
+
+- **member1**:
+
+  ```shell
+  kubectl --context member1 get deploy -o wide
+  NAME           READY   UP-TO-DATE   AVAILABLE   AGE     CONTAINERS   IMAGES         SELECTOR
+  nginx-deploy   2/2     2            2           5m24s   nginx        nginx:latest   app=nginx
+
+  kubectl --context member1 get svc -o wide
+  NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE   SELECTOR
+  nginx-svc    NodePort    10.13.161.255   <none>        80:30000/TCP   54s   app=nginx
+  ```
+
+- **member2**:
+
+  ```shell
+  kubectl --context member2 get deploy -o wide
+  NAME           READY   UP-TO-DATE   AVAILABLE   AGE     CONTAINERS   IMAGES         SELECTOR
+  nginx-deploy   2/2     2            2           5m24s   nginx        nginx:latest   app=nginx
+
+  kubectl --context member2 get svc -o wide
+  NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE   SELECTOR
+  nginx-svc    NodePort    10.13.161.255   <none>        80:30000/TCP   54s   app=nginx
+  ```
+
+This confirms that the higher priority `PropagationPolicy` has effectively propagated the `nginx` application resources to both `member1` and `member2` clusters, meeting the desired propagation requirements.
+
+---