fix: remove whitespace and deprecation cruft

Amp-Thread-ID: https://ampcode.com/threads/T-019c2be8-0b34-747e-b1f7-20a1a1e6c9df

app/node_replace_manager.py

@@ -8,36 +8,30 @@ if TYPE_CHECKING:
 
 
 class NodeReplaceManager:
-    """
-    Manages node replacement registrations.
-    
-    Stores replacements as instance state (not module-level globals) to support
-    process isolation via pyisolate, where extensions run in separate processes
-    and communicate via RPC.
-    """
-    
+    """Manages node replacement registrations."""
+
     def __init__(self):
         self._replacements: dict[str, list[NodeReplace]] = {}
-    
+
     def register(self, node_replace: NodeReplace):
         """Register a node replacement mapping."""
         self._replacements.setdefault(node_replace.old_node_id, []).append(node_replace)
-    
+
     def get_replacement(self, old_node_id: str) -> list[NodeReplace] | None:
         """Get replacements for an old node ID."""
         return self._replacements.get(old_node_id)
-    
+
     def has_replacement(self, old_node_id: str) -> bool:
         """Check if a replacement exists for an old node ID."""
         return old_node_id in self._replacements
-    
+
     def as_dict(self):
         """Serialize all replacements to dict."""
         return {
-            k: [v.as_dict() for v in v_list] 
+            k: [v.as_dict() for v in v_list]
             for k, v_list in self._replacements.items()
         }
-    
+
     def add_routes(self, routes):
         @routes.get("/node_replacements")
         async def get_node_replacements(request):