docs: Clarify that what the scope draws is an open path

python_payload/mypystubs/ctx.pyi

@@ -323,7 +323,8 @@ class Context(Protocol):
     def scope(self) -> "Context":
         """
         Draw an audio 'oscilloscope'-style visualizer at -120,-120,120,120
-        bounding box.
+        bounding box as an open path with starting point at x=-120 and ending
+        at x=120.
 
         Needs to be stroked/filled afterwards.
         """