log: demote all per-node lifecycle INFO logs to DEBUG

Extend the docker_vm / base_node demotion to the remaining node types
and supporting layers:

  qemu_vm: MAC, adapters, disk image, RAM, priority, NIO added, created
  iou_vm:  application ID, adapters, serial, image, RAM, NIO added
  dynamips router: created, adapter, RAM, NVRAM, IOS, idle-PC, disk,
    MAC, NIO bound; hypervisor create/start/connect; nio_udp created
  builtin: ethernet_switch/hub, cloud, nat — created, NIO bound
  ubridge: hypervisor start/connect

At multi-node scale these per-node lines flood the log. Only the
project-open progress summary (loaded N nodes / creating N links)
now remains at INFO alongside genuinely exceptional events.

gns3server/api/routes/compute/qemu_nodes.py

@@ -83,7 +83,7 @@ async def create_qemu_node(project_id: UUID, node_data: schemas.QemuCreate) -> s
     for disk_index, drive in enumerate(drives):
         disk_image_backing_file = node_data.get(f"hd{drive}_disk_image_backing_file")
         if disk_image_backing_file:
-            log.info(f"Updating disk image for drive {drive} with backing file {disk_image_backing_file}")
+            log.debug(f"Updating disk image for drive {drive} with backing file {disk_image_backing_file}")
             node_data[f"hd{drive}_disk_image"] = disk_image_backing_file
 
     for name, value in node_data.items():