fix: chmod +x in genapkovl to fix permissions regardless of git filemode on VM

- genapkovl now explicitly chmod +x init.d/* and usr/local/bin/* after cp
- add bee-net-restart command (short name, no .sh) and /etc/profile.d/bee.sh for PATH
- udhcpc: add & to ensure non-blocking even when DHCP responds immediately
- motd: short commands without paths

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

iso/overlay-debug/usr/local/bin/bee-net-restart

@@ -0,0 +1,8 @@
+#!/bin/sh
+# bee-net-restart.sh — bring up all physical interfaces via DHCP (manual re-run)
+
+for iface in $(ip -o link show | awk -F': ' '{print $2}' | grep -v '^lo$' | grep -vE '^(docker|virbr|veth|tun|tap|br-|bond|dummy)'); do
+    echo "[$iface] bringing up..."
+    ip link set "$iface" up 2>/dev/null
+    udhcpc -i "$iface" -t 5 -T 3
+done