refactor: 积分系统拆分为独立 erp-points crate

- 新建 erp-points crate（8 Entity + account/product service + handler）
- 商品 CRUD 和账户管理完整实现，订单/签到/规则端点暂返回 501
- 注册到 workspace + erp-server 路由 /api/v1/points/*
- API 路径不变，前端无需修改

Cargo.lock

@@ -1625,6 +1625,25 @@ dependencies = [
  "wit-bindgen 0.55.0",
 ]
 
+[[package]]
+name = "erp-points"
+version = "0.1.0"
+dependencies = [
+ "async-trait",
+ "axum",
+ "chrono",
+ "erp-core",
+ "sea-orm",
+ "serde",
+ "serde_json",
+ "thiserror 2.0.18",
+ "tokio",
+ "tracing",
+ "utoipa",
+ "uuid",
+ "validator",
+]
+
 [[package]]
 name = "erp-server"
 version = "0.1.0"
@@ -1640,6 +1659,7 @@ dependencies = [
  "erp-health",
  "erp-message",
  "erp-plugin",
+ "erp-points",
  "erp-server-migration",
  "erp-workflow",
  "moka",