Set extruder index

For the command `set_toolhead_temperature`, assign index 0.

Author: antonysigma

mbotmake2/transformers/toolpath.py

@@ -74,7 +74,7 @@ def visit_ToolheadTemperature(self, _, visited_children):
                 print(f"Overriding extruder temperature: {self.extruder_temperature} -> {temperature}")
             self.extruder_temperature = temperature
 
-        self.commands.append(Command("set_toolhead_temperature", {"temperature": temperature}))
+        self.commands.append(Command("set_toolhead_temperature", {"temperature": temperature, "index": 0}))
 
     def visit_Move(self, node, visited_children) -> None:
         _, (coords,) = visited_children