Fix ComfyAPI initialization for base async case, move on_load to be called before get_node_list

comfy_api/latest/__init__.py

@@ -22,14 +22,17 @@ class ComfyAPI_latest(ComfyAPIBase):
     VERSION = "latest"
     STABLE = False
 
+    def __init__(self):
+        super().__init__()
+        self.node_replacement = self.NodeReplacement()
+        self.execution = self.Execution()
+
     class NodeReplacement(ProxiedSingleton):
         async def register(self, node_replace: 'node_replace.NodeReplace') -> None:
             """Register a node replacement mapping."""
             from server import PromptServer
             PromptServer.instance.node_replace_manager.register(node_replace)
 
-    node_replacement: NodeReplacement
-
     class Execution(ProxiedSingleton):
         async def set_progress(
             self,
@@ -82,8 +85,6 @@ class ComfyAPI_latest(ComfyAPIBase):
                 image=to_display,
             )
 
-    execution: Execution
-
 class ComfyExtension(ABC):
     async def on_load(self) -> None:
         """