pcloud: add support for real-time updates in mount

Co-authored-by: masrlinu <5259918+masrlinu@users.noreply.github.com>

docs/content/pcloud.md

@@ -173,6 +173,31 @@ So if the folder you want rclone to use your is "My Music/", then use the return
 id from ```rclone lsf``` command (ex. `dxxxxxxxx2`) as the `root_folder_id` variable
 value in the config file.
 
+### Change notifications and mounts
+
+The pCloud backend supports real‑time updates for rclone mounts via change
+notifications. rclone uses pCloud’s diff long‑polling API to detect changes and
+will automatically refresh directory listings in the mounted filesystem when
+changes occur.
+
+Notes and behavior:
+
+- Works automatically when using `rclone mount` and requires no additional
+  configuration.
+- Notifications are directory‑scoped: when rclone detects a change, it refreshes
+  the affected directory so new/removed/renamed files become visible promptly.
+- Updates are near real‑time. The backend uses a long‑poll with short fallback
+  polling intervals, so you should see changes appear quickly without manual
+  refreshes.
+
+If you want to debug or verify notifications, you can use the helper command:
+
+```bash
+rclone test changenotify remote:
+```
+
+This will log incoming change notifications for the given remote.
+
 <!-- autogenerated options start - DO NOT EDIT - instead edit fs.RegInfo in backend/pcloud/pcloud.go and run make backenddocs to verify --> <!-- markdownlint-disable-line line-length -->
 ### Standard options