feat: show IOL-style interface names on iol-runner ports

Name ports after the IOL interface they map to (Ethernet0/0, one 4-port
unit per adapter range) via the _get_container_ifname override point, so
the GNS3 UI matches the IOS CLI. Display only — the flat adapter number
remains the socket index.

gns3server/compute/docker/iol_docker_vm.py

@@ -105,6 +105,15 @@ class IOLDockerVM(VendorDockerVM):
                 volumes.append(needed)
         return volumes
 
+    def _get_container_ifname(self, adapter_number):
+        """
+        Override: name ports after the IOL interface they map to
+        (Ethernet0/0, Ethernet0/1, … — a new 4-port unit every four
+        adapters), so what the GNS3 UI shows matches the IOS CLI. Wiring is
+        unaffected: the flat adapter number remains the socket index.
+        """
+        return f"Ethernet{adapter_number // 4}/{adapter_number % 4}"
+
     async def start(self):
 
         await self._prepare_iol_runtime()