obs-frontend-api,UI,docs: Add dock API that ask for unique object name

obs_frontend_add_dock() is deprecated in favor of
obs_frontend_add_dock_by_id()

docs/sphinx/reference-frontend-api.rst

@@ -447,6 +447,33 @@ Functions
    :param dock: QDockWidget to add/create
    :return: A pointer to the added QAction
 
+.. deprecated:: 29.1
+   Prefer :c:func:`obs_frontend_add_dock_by_id()` instead.
+
+---------------------------------------
+
+.. function:: bool obs_frontend_add_dock_by_id(const char *id, const char *title, void *widget)
+
+   Adds a dock with the widget to the UI with a toggle in the Docks
+   menu.
+
+   Note: Use :c:func:`obs_frontend_remove_dock` to remove the dock
+         and the id from the UI.
+
+   :param id: Unique identifier of the dock
+   :param title: Window title of the dock
+   :param widget: QWidget to insert in the dock
+   :return: *true* if the dock was added, *false* if the id was already
+            used
+
+---------------------------------------
+
+.. function:: void obs_frontend_remove_dock(const char *id)
+
+   Removes the dock with this id from the UI.
+
+   :param id: Unique identifier of the dock to remove.
+
 ---------------------------------------
 
 .. function:: void obs_frontend_add_event_callback(obs_frontend_event_cb callback, void *private_data)