Geometry Nodes: change idnames of experimental bundle and closure nodes

This removes the "Geometry" part from their name because we want to use them in
other node tree types too (see #141936).

Usually, we don't change idnames because they are the primary identifier of
nodes and is expected to stay the same. Since they are generally not shown to
users (just Python developers), it's also not urgent to change them. However, in
this specific case we have the opportunity to update the idname before the node
becomes an official feature, so it's not as bad to change it.

This patch has full backward compatibility, but no forward compatibility (for
files that used the experimental feature).

Pull Request: https://projects.blender.org/blender/blender/pulls/143823

scripts/startup/bl_operators/node.py

@@ -286,8 +286,8 @@ class NODE_OT_add_closure_zone(NodeAddZoneOperator, Operator):
     bl_label = "Add Closure Zone"
     bl_options = {'REGISTER', 'UNDO'}
 
-    input_node_type = "GeometryNodeClosureInput"
-    output_node_type = "GeometryNodeClosureOutput"
+    input_node_type = "NodeClosureInput"
+    output_node_type = "NodeClosureOutput"
     add_default_geometry_link = False