Add kiosk setup and deployment scripts (Phases 5 + 9)

Phase 5 — RPi Kiosk:
- setup_kiosk.sh: full RPi OS Lite setup (X11, Chromium kiosk mode,
  auto-login, DPMS disabled, GPU memory split, screen rotation)
- kiosk.service: systemd unit for reliable auto-start
- update_kiosk.sh: reconfigure URL/rotation/resolution without re-setup
- Handles both Bullseye and Bookworm RPi OS versions

Phase 9 — Hardening + Deployment:
- install.sh: full server setup (apt/pacman, vigilar user, venv,
  directories, permissions, mosquitto config, systemd units)
- gen_cert.sh: TLS cert via mkcert or openssl fallback
- gen_vapid_keys.sh: VAPID keys for Web Push notifications
- setup_nut.sh: NUT configuration with USB UPS auto-detection
- backup.sh: SQLite snapshot + config archive, cron-ready
- uninstall.sh: clean removal with data preservation option
- vigilar.service: hardened systemd unit (ProtectSystem, NoNewPrivileges,
  PrivateTmp, syscall filtering)
- vigilar-mosquitto.conf: localhost-only MQTT broker config

All scripts idempotent, bash -n validated, support Debian + Arch.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

systemd/vigilar.service

@@ -0,0 +1,53 @@
+[Unit]
+Description=Vigilar Home Security System
+Documentation=https://github.com/vigilar/vigilar
+After=network.target mosquitto.service
+Requires=mosquitto.service
+Wants=nut-monitor.service
+
+[Service]
+Type=simple
+User=vigilar
+Group=vigilar
+
+Environment=VIGILAR_CONFIG=/etc/vigilar/vigilar.toml
+ExecStart=/opt/vigilar/venv/bin/vigilar start --config /etc/vigilar/vigilar.toml
+
+Restart=on-failure
+RestartSec=10
+WatchdogSec=120
+
+# Security hardening
+NoNewPrivileges=yes
+ProtectSystem=strict
+ProtectHome=yes
+PrivateTmp=yes
+PrivateDevices=yes
+ProtectKernelModules=yes
+ProtectKernelTunables=yes
+ProtectKernelLogs=yes
+ProtectControlGroups=yes
+ProtectClock=yes
+ProtectHostname=yes
+RestrictNamespaces=yes
+RestrictRealtime=yes
+RestrictSUIDSGID=yes
+LockPersonality=yes
+MemoryDenyWriteExecute=no
+SystemCallArchitectures=native
+SystemCallFilter=@system-service
+SystemCallFilter=~@privileged @resources
+
+# Allow write to data directories
+ReadWritePaths=/var/vigilar/data /var/vigilar/recordings /var/vigilar/hls
+
+# Read-only access to config and secrets
+ReadOnlyPaths=/etc/vigilar
+
+# Logging
+StandardOutput=journal
+StandardError=journal
+SyslogIdentifier=vigilar
+
+[Install]
+WantedBy=multi-user.target