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

crates/erp-server/src/main.rs

@@ -349,6 +349,14 @@ async fn main() -> anyhow::Result<()> {
         "AI module initialized"
     );
 
+    // Initialize points module
+    let points_module = erp_points::PointsModule;
+    tracing::info!(
+        module = points_module.name(),
+        version = points_module.version(),
+        "Points module initialized"
+    );
+
     // Initialize module registry and register modules
     let registry = ModuleRegistry::new()
         .register(auth_module)
@@ -356,7 +364,8 @@ async fn main() -> anyhow::Result<()> {
         .register(workflow_module)
         .register(message_module)
         .register(health_module)
-        .register(ai_module);
+        .register(ai_module)
+        .register(points_module);
     tracing::info!(
         module_count = registry.modules().len(),
         "Modules registered"
@@ -535,6 +544,7 @@ async fn main() -> anyhow::Result<()> {
         .merge(erp_plugin::module::PluginModule::protected_routes())
         .merge(erp_health::HealthModule::protected_routes())
         .merge(erp_ai::AiModule::protected_routes())
+        .merge(erp_points::PointsModule::protected_routes())
         .merge(handlers::audit_log::audit_log_router())
         .route(
             "/upload",

crates/erp-server/src/state.rs

@@ -122,3 +122,13 @@ impl FromRef<AppState> for erp_ai::AiState {
         state.ai_state.clone()
     }
 }
+
+/// Allow erp-points handlers to extract their required state.
+impl FromRef<AppState> for erp_points::PointsState {
+    fn from_ref(state: &AppState) -> Self {
+        Self {
+            db: state.db.clone(),
+            event_bus: state.event_bus.clone(),
+        }
+    }
+}