fixed new gui removing marker annotations when creating new sessions

daemon/core/gui/graph/graph.py

@@ -534,7 +534,7 @@ class CanvasGraph(tk.Canvas):
                     y + r,
                     fill=self.app.toolbar.marker_tool.color,
                     outline="",
-                    tags="marker",
+                    tags=tags.MARKER,
                 )
                 return
             if selected is None:

daemon/core/gui/graph/tags.py

@@ -10,6 +10,7 @@ NODE = "node"
 WALLPAPER = "wallpaper"
 SELECTION = "selectednodes"
 THROUGHPUT = "throughput"
+MARKER = "marker"
 ABOVE_WALLPAPER_TAGS = [
     GRIDLINE,
     SHAPE,
@@ -33,4 +34,5 @@ COMPONENT_TAGS = [
     SELECTION,
     SHAPE,
     SHAPE_TEXT,
+    MARKER,
 ]