feat: 新增客户管理全模块功能

实现客户信息、客户部门、客户账号三个子模块的完整CRUD，包含：
1. 数据库实体、DTO、控制器、服务层代码
2. RBAC权限映射与菜单种子数据扩展
3. 前端路由与API封装
4. 数据权限隔离与鉴权逻辑
5. 配套工具脚本与测试验证清单

server/src/entity/customer.entity.ts

@@ -0,0 +1,126 @@
+import { Column, Model, Table, DataType, CreatedAt, UpdatedAt, HasMany } from "sequelize-typescript";
+import CustomerDepartment from "./customer_department.entity";
+import CustomerAccount from "./customer_account.entity";
+
+@Table({
+	tableName: "customer",
+	comment: "客户信息表",
+	timestamps: true,
+	createdAt: "created_at",
+	updatedAt: "updated_at",
+	indexes: [
+		{ name: "idx_customer_name", fields: ["customer_name"] },
+		{ name: "idx_customer_salesman", fields: ["salesman_id"] },
+		{ name: "idx_customer_status", fields: ["status"] },
+		{ unique: true, name: "uk_customer_no", fields: ["customer_no"] }
+	]
+})
+export default class Customer extends Model {
+	@Column({
+		type: DataType.BIGINT,
+		autoIncrement: true,
+		primaryKey: true
+	})
+	id!: number;
+
+	@Column({
+		type: DataType.STRING(64),
+		allowNull: false,
+		unique: true,
+		field: "customer_no",
+		comment: "客户业务编号(KH+YYYYMMDD+序号)"
+	})
+	customerNo!: string;
+
+	@Column({
+		type: DataType.STRING(128),
+		allowNull: false,
+		comment: "客户名称"
+	})
+	customerName!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		comment: "省"
+	})
+	province!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		comment: "市"
+	})
+	city!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		comment: "区"
+	})
+	district!: string;
+
+	@Column({
+		type: DataType.STRING(256),
+		comment: "详细地址"
+	})
+	address!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		field: "contact_person",
+		comment: "联系人"
+	})
+	contactPerson!: string;
+
+	@Column({
+		type: DataType.STRING(20),
+		field: "contact_phone",
+		comment: "联系电话"
+	})
+	contactPhone!: string;
+
+	@Column({
+		type: DataType.STRING(10),
+		field: "postal_code",
+		comment: "邮编"
+	})
+	postalCode!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		comment: "传真"
+	})
+	fax!: string;
+
+	@Column({
+		type: DataType.STRING(32),
+		field: "customer_level",
+		comment: "客户级别(学校/医院/企业等)"
+	})
+	customerLevel!: string;
+
+	@Column({
+		type: DataType.SMALLINT,
+		allowNull: false,
+		defaultValue: 1,
+		comment: "状态:1意向/2签约/3运维中/4终止"
+	})
+	status!: number;
+
+	@Column({
+		type: DataType.BIGINT,
+		field: "salesman_id",
+		comment: "负责业务员(关联sys_user.id)，references->sys_user.id"
+	})
+	salesmanId!: number;
+
+	@HasMany(() => CustomerDepartment, { foreignKey: "customerId" })
+	customerDepartments!: CustomerDepartment[];
+
+	@HasMany(() => CustomerAccount, { foreignKey: "customerId" })
+	customerAccounts!: CustomerAccount[];
+
+	@CreatedAt
+	created_at!: Date;
+
+	@UpdatedAt
+	updated_at!: Date;
+}