feat(pl): 运费结算审批分流与车辆挂车号等 PL 能力完善

拆分运费审批/出款页面，补充结算发票附件与菜单 SQL，并同步前后端模型与车辆相关展示。

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/sql/20260628_pl_freight_settlement_invoice_attachment.sql

@@ -0,0 +1,3 @@
+-- 运费结算：发票附件字段
+ALTER TABLE `pl_freight_settlement`
+  ADD COLUMN `invoice_attachment_urls` text DEFAULT NULL COMMENT '发票附件URLs，逗号分隔' AFTER `invoice_date`;