Add exit node selection and auto-apply behavior documentation (#415)

* Add exit node selection and auto-apply behavior documentation, including new image for Skip Auto Apply feature.

* Add exit node auto-apply feature documentation and new image for exit node configuration.

* Add documentation for existing exit node routes and their auto-apply behavior, clarifying that routes created before the feature's introduction are treated as auto-applied by default.

Author: hakansa

public/docs-static/img/how-to-guides/exit-node-auto-apply.png

@@ -31,9 +31,27 @@ Peers within the specified distribution group are configured to send their Inter
 VPN.
 This setup is activated as soon as the routing peer is connected.
 
-### Routing Peer Selection
+### Exit Node Selection and Auto Apply Behavior
 
-Currently, this is exclusively configured through the dashboard and cannot be influenced by the client.
+Administrators configure exit nodes from the dashboard, and can optionally mark the default route (0.0.0.0/0) as selected by default. Clients will then auto-apply the selected exit node if the route is configured with **Auto Apply** or the user has made a local choice on the device.
+
+- **Auto Apply**: when enabled on an exit node route, clients will auto-apply that exit node. Users can still manually disable it from the client if they choose to use that exit node.
+- **Client override**: if a user selects or deselects an exit node on their device, that local choice takes precedence over the management server’s preference. This includes the ability to deselect a forced/selected route sent by management.
+
+<Note>
+  Management can provide preferences for exit node selection, but the client user’s explicit selection or deselection is always respected on that device.
+</Note>
+
+<Note>
+  Exit node auto-apply feature requires NetBird client **v0.55.0** or later.
+</Note>
+
+### Existing exit node routes
+
+Exit node routes that existed before the Auto Apply feature are treated as if **Auto Apply** is enabled by default. This preserves previous behavior where exit nodes were applied automatically when distributed.
+
+- Clients running v0.55.0 or later will auto-apply these existing routes unless the user has explicitly selected/deselected an exit node on the device.
+- Administrators can edit any exit node route in the dashboard to change its Auto Apply setting at any time.
 
 ## Configuration Steps
 
@@ -60,12 +78,17 @@ Hit the `Add Exit Node` button to configure the peer as an exit node routing pee
 In the opened window, specify which peers should use the default route by assigning one or more distribution groups.
 These peers will automatically route their internet traffic through the routing peer upon its connection.
 
-
 <p>
     <img src="/docs-static/img/how-to-guides/netbird-peers-add-exit-node.png" alt="add-exit-node-view"
          className="imagewrapper-big"/>
 </p>
 
+If you want exit nodes to be available without being automatically enabled on clients, enable the **Auto Apply** option. When Auto Apply is on, clients will auto-apply the exit node, but users can manually disable it from the client.
+
+<p>
+    <img src="/docs-static/img/how-to-guides/exit-node-auto-apply.png" alt="exit-node-auto-apply" className="imagewrapper-big"/>
+</p>
+
 Then hit the `Add Exit Node` button to complete the configuration.
 
 The routing peer is automatically set up to handle and route traffic it receives from connected peers. Masquerading