chore(home.server): exclude bootshorn and windows-backup from backups

Together 2 TB on home.backups; the bootshorn recordings are being
reduced to their findings, the windows backup moves elsewhere.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RywMtsL8qXG7GDY3MHq9Uh

nodes/home.server.py

@@ -211,6 +211,11 @@
                 'hdd/bootshorn': {
                     'mountpoint': '/hdd/bootshorn',
                     'dedup': 'on',
+                    'backup': False,
+                },
+                # dataset from bundle samba (share windows-backup)
+                'hdd/samba/windows-backup': {
+                    'backup': False,
                 },
             },
         },