deploy: use nix-flake-archive instead of rsync to upload

pkgs/clan-cli/clan_cli/machines/update.py

@@ -1,5 +1,6 @@
 import argparse
 import json
+import os
 import subprocess
 
 from ..ssh import Host, HostGroup, HostKeyCheck
@@ -13,11 +14,13 @@ def deploy_nixos(hosts: HostGroup) -> None:
     def deploy(h: Host) -> None:
         target = f"{h.user or 'root'}@{h.host}"
         ssh_arg = f"-p {h.port}" if h.port else ""
+        env = os.environ.copy()
+        env["NIX_SSHOPTS"] = ssh_arg
         res = h.run_local(
             ["nix", "flake", "archive", "--to", f"ssh://{target}", "--json"],
             check=True,
             stdout=subprocess.PIPE,
-            extra_env=dict(NIX_SSHOPTS=ssh_arg),
+            extra_env=env
         )
         data = json.loads(res.stdout)
         path = data["path"]