Install OpenSSH Server from the Win32-OpenSSH zip

Carry the zip for the host architecture in the seed ISO and add
06-Install-OpenSSH-Zip-Admin.bat, which installs from it instead of
Windows Update. Update vm-images.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

run-windows11.py

@@ -304,11 +304,17 @@ if installing_from_iso:
     seed_sources = [seed_dir / "Autounattend.xml", seed_dir / "Configure-Windows.ps1",
                     *sorted(seed_dir.glob("[0-9][0-9]-*.bat"))]
 
+    # The seed carries the OpenSSH zip for this architecture; build-seed.sh
+    # downloads it when missing.
+    seed_sources.append(Path(capture(
+        [str(image_downloader), "--print-path", "openssh-win"])))
+
     def newer_than_seed(source):
         # Mirrors bash `-nt`: true if source exists and is newer than seed_iso.
         return source.exists() and source.stat().st_mtime > seed_iso.stat().st_mtime
 
-    if not seed_iso.is_file() or any(newer_than_seed(s) for s in seed_sources):
+    if not seed_iso.is_file() or not seed_sources[-1].is_file() \
+            or any(newer_than_seed(s) for s in seed_sources):
         run([str(script_dir / "seediso" / "windows11" / "build-seed.sh"), str(seed_iso), host_arch])
 
 if pid_file.is_file():