fix: refresh stale cellular source IP and resolve cpxy symlink BASE

WWAN re-dial often keeps iface name (wwan0) but changes private IP.
Stale inet4_bind_address then makes SOCKS rep=0x01 while the panel still
looks healthy. generate/cpxy now re-read live source IP on each regenerate.

Also fix /usr/local/bin/cpxy symlink: dirname($0) became /usr/local and
broke rebind/generate (missing lib.sh).

scripts/generate.sh

@@ -13,9 +13,22 @@ cell="$(resolve_cellular 2>/dev/null || true)"
 if [[ -z "$cell" ]]; then
   resolve_cellular >/dev/null || true
 fi
-src_ip="${CELLULAR_SOURCE_IP:-}"
-if [[ -z "$src_ip" && -n "$cell" ]]; then
-  src_ip="$(detect_source_ip "$cell" || true)"
+
+# 始终以当前网卡实 IP 为准：WWAN 重拨后 iface 名常不变，但 CELLULAR_SOURCE_IP 会过期。
+# 过期的 inet4_bind_address 会导致 sing-box 出站失败 → 客户端 SOCKS rep=0x01。
+live_src=""
+if [[ -n "$cell" ]]; then
+  live_src="$(detect_source_ip "$cell" || true)"
+fi
+src_ip="${live_src:-${CELLULAR_SOURCE_IP:-}}"
+if [[ -n "$cell" && -n "$live_src" && "${CELLULAR_SOURCE_IP:-}" != "$live_src" ]]; then
+  info "源 IP 已漂移: ${CELLULAR_SOURCE_IP:-<空>} → $live_src，写回 settings"
+  persist_cellular_to_settings "${CONFIG_FILE:-$ROOT_DIR/etc/settings.conf}" "$cell" "$live_src" || true
+  # 兼容 live 安装布局：settings 在 etc/
+  if [[ -f /opt/cellular-proxy/etc/settings.conf ]]; then
+    persist_cellular_to_settings /opt/cellular-proxy/etc/settings.conf "$cell" "$live_src" || true
+  fi
+  CELLULAR_SOURCE_IP="$live_src"
 fi
 
 if [[ -z "$cell" ]]; then