fix(dock_area): save/restore state is saved in config

bec_widgets/cli/client.py

@@ -1,9 +1,8 @@
 # This file was automatically generated by generate_cli.py
 
+from bec_widgets.cli.client_utils import rpc_call, RPCBase, BECGuiClientMixin
 from typing import Literal, Optional, overload
 
-from bec_widgets.cli.client_utils import BECGuiClientMixin, RPCBase, rpc_call
-
 
 class BECPlotBase(RPCBase):
     @property
@@ -1528,6 +1527,16 @@ class BECDock(RPCBase):
 
 
 class BECDockArea(RPCBase, BECGuiClientMixin):
+    @property
+    @rpc_call
+    def config_dict(self) -> "dict":
+        """
+        Get the configuration of the widget.
+
+        Returns:
+            dict: The configuration of the widget.
+        """
+
     @property
     @rpc_call
     def panels(self) -> "dict":

bec_widgets/widgets/dock/dock_area.py

@@ -16,10 +16,14 @@ from .dock import BECDock, DockConfig
 
 class DockAreaConfig(ConnectionConfig):
     docks: dict[str, DockConfig] = Field({}, description="The docks in the dock area.")
+    docks_state: Optional[dict] = Field(
+        None, description="The state of the docks in the dock area."
+    )
 
 
 class BECDockArea(BECConnector, DockArea):
     USER_ACCESS = [
+        "config_dict",
         "panels",
         "save_state",
         "remove_dock",
@@ -81,7 +85,7 @@ class BECDockArea(BECConnector, DockArea):
             extra(str): Extra docks that are in the dockarea but that are not mentioned in state will be added to the bottom of the dockarea, unless otherwise specified by the extra argument.
         """
         if state is None:
-            state = self._last_state
+            state = self.config.docks_state
         self.restoreState(state, missing=missing, extra=extra)
 
     def save_state(self) -> dict:
@@ -91,8 +95,9 @@ class BECDockArea(BECConnector, DockArea):
         Returns:
             dict: The state of the dock area.
         """
-        self._last_state = self.saveState()
-        return self._last_state
+        last_state = self.saveState()
+        self.config.docks_state = last_state
+        return last_state
 
     def remove_dock(self, name: str):
         """