Geometry Nodes' Add > Input > Import menu includes file format items
such as "Standford PLY (.ply)", "STL (.stl)", "Text (.txt)". The
latter needs to be translated because "Text" is a generic format.
These items are declared using a custom function
`node_add_menu.add_node_type`, with a `label` argument. This commit
adds the `label` argument to the function arguments that can be
extracted from specific node declaration functions, and specifies the
argument position for each:
"add_node_type", "add_node_type_with_outputs", "add_simulation_zone",
"add_repeat_zone", "add_foreach_geometry_element_zone",
"add_closure_zone".
There is currently no facility to specify a translation context but it
could be easily added if the need arises.
Most of these functions do not actually declare new, unique messages,
but it could happen in the future. In addition, two messages were
extracted using manual `iface_()` calls, which are no longer needed
after this change.
Reported by Ye Gui in #43295.
0ba83d8958