Pi: WiFi hotspot (AP on wlan0, 10.42.0.1) + hotspot/wifi toggle scripts + README

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

scripts/wifi-join.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# Fa entrare il Pi in una rete WiFi normale (client) — disattiva l'hotspot.
+# Uso: bash scripts/wifi-join.sh "NomeRete" "password"
+# Per tornare hotspot: bash scripts/hotspot-on.sh
+if [ -z "$1" ]; then echo "Uso: $0 <SSID> [password]"; exit 1; fi
+sudo nmcli device wifi connect "$1" ${2:+password "$2"} ifname wlan0
+echo "Connesso a '$1'. IP wlan0: $(ip -4 -br addr show wlan0 | awk '{print $3}')"