chore: move close node to network

Signed-off-by: Manish Dait <daitmanish88@gmail.com>

Author: manishdait

src/hiero_sdk_python/client/client.py

@@ -220,12 +220,7 @@ def close(self) -> None:
         Closes any open gRPC channels and frees resources.
         Call this when you are done using the Client to ensure a clean shutdown.
         """
-        self.network.close_mirror_connection()
-
-        # Fix: Close all consensus node channels
-        if self.network and self.network.nodes:
-            for node in self.network.nodes:
-                node._close()
+        self.network._close()
 
     def set_transport_security(self, enabled: bool) -> Client:
         """

src/hiero_sdk_python/client/network.py

@@ -429,14 +429,18 @@ def _mark_node_healthy(self, node: _Node) -> None:
         if node not in self._healthy_nodes:
             self._healthy_nodes.append(node)
 
-    def close_mirror_connection(self):
+    def _close(self):
         """Safely closes the mirror gRPC channel."""
         if self._mirror_channel is not None:
             self._mirror_channel.close()
 
         self._mirror_channel = None
         self._mirror_stub = None
 
+        if self.nodes:
+            for node in self.nodes:
+                node._close()
+
     def get_mirror_stub(self) -> mirror_consensus_grpc.ConsensusServiceStub:
         """Returns the mirror stub."""
         if self._mirror_stub is None: