[req-changes] Added device config status

Author: pandafy

docs/index.rst

@@ -35,6 +35,7 @@ the OpenWISP architecture.
     :maxdepth: 1
 
     user/intro.rst
+    user/device-config-status.rst
     user/templates.rst
     user/variables.rst
     user/device-groups.rst

docs/user/device-config-status.rst

@@ -0,0 +1,37 @@
+Device Configuration Status
+===========================
+
+The device's configuration status (`Device.config.status`) indicates the
+current state of the configuration as managed by OpenWISP. The possible
+statuses and their meanings are outlined below:
+
+``modified``
+------------
+
+The device configuration has been updated in OpenWISP, but these changes
+have not yet been applied to the device. The device is pending an update.
+
+``applied``
+-----------
+
+The device has successfully applied the configuration changes made in
+OpenWISP. The current configuration on the device matches the latest
+changes.
+
+``error``
+---------
+
+An issue occurred while applying the configuration to the device, causing
+the device to revert to its previous configuration to prevent errors.
+
+``deactivating``
+----------------
+
+The device is in the process of being deactivated. The configuration is
+scheduled to be removed from the device.
+
+``deactivated``
+---------------
+
+The device has been deactivated. Its configuration has been completely
+removed, and it is no longer managed by OpenWISP.