Add web GUI, docs, scripts, and 5G router config

- Web app (Flask): status, config, firewall, logs, users, restart
- Docs: AT commands, deploy, DNS, quickstart, web GUI
- Scripts: connect, deploy, diag, healthcheck, modem-status, speedtest, status, troubleshoot
- Init and iptables: 5g-router, 5g-webgui, rules.v4
- CHANGELOG, TODO, REVISION; config and README updates

scripts/status-5g.sh

@@ -0,0 +1,44 @@
+#!/bin/sh
+# Alpine 5G Router – status (modem, interface, default route, last speedtest)
+# Usage: status-5g.sh [--json] (optional machine-readable output)
+# Rev: 1  (see REVISION in repo root)
+
+CONFIG="/etc/5g-router.conf"
+WAN_IF="${WAN_IF:-eth1}"
+LAN_IF="${LAN_IF:-eth0.100}"
+AT_PORT="${AT_PORT:-/dev/ttyUSB1}"
+[ -f "$CONFIG" ] && . "$CONFIG"
+
+SPEEDTEST_LOG="/var/log/speedtest-5g.log"
+MODEM_USB=$(lsusb 2>/dev/null | grep -i fibocom | head -1)
+DEFAULT_ROUTE=$(ip route show default 2>/dev/null | head -1)
+WAN_IP=$(ip -4 addr show "$WAN_IF" 2>/dev/null | grep -oE 'inet [0-9.]+' | awk '{print $2}')
+WAN_STATE=$(ip link show "$WAN_IF" 2>/dev/null | grep -oE 'state [A-Z]+' | awk '{print $2}')
+LAST_SPEEDTEST=""
+[ -f "$SPEEDTEST_LOG" ] && LAST_SPEEDTEST=$(tail -5 "$SPEEDTEST_LOG" 2>/dev/null)
+
+if [ "$1" = "--json" ]; then
+    echo "{"
+    echo "  \"modem_usb\": \"${MODEM_USB:-none}\","
+    echo "  \"wan_interface\": \"$WAN_IF\","
+    echo "  \"wan_state\": \"${WAN_STATE:-unknown}\","
+    echo "  \"wan_ip\": \"${WAN_IP:-}\","
+    echo "  \"default_route\": \"${DEFAULT_ROUTE:-none}\","
+    echo "  \"at_port\": \"$AT_PORT\","
+    echo "  \"at_available\": \"$([ -c \"$AT_PORT\" ] && echo yes || echo no)\""
+    echo "}"
+    exit 0
+fi
+
+echo "=== 5G Router Status ==="
+echo "Modem:    ${MODEM_USB:-not detected}"
+echo "AT port:  $AT_PORT ($([ -c "$AT_PORT" ] && echo "available" || echo "not available"))"
+echo "WAN:      $WAN_IF state=$WAN_STATE ip=$WAN_IP"
+echo "Default:  $DEFAULT_ROUTE"
+echo ""
+echo "--- Last speedtest ---"
+if [ -n "$LAST_SPEEDTEST" ]; then
+    echo "$LAST_SPEEDTEST"
+else
+    echo "(none – run speedtest-cli --simple and redirect to $SPEEDTEST_LOG)"
+fi