feat: 新增目标管理功能模块

实现目标管理的完整功能，包括数据库表设计、API接口、业务逻辑和文档说明。支持用户创建、管理和跟踪个人目标，提供增删改查操作及目标完成记录功能。

src/goals/goals.module.ts

@@ -0,0 +1,16 @@
+import { Module } from '@nestjs/common';
+import { SequelizeModule } from '@nestjs/sequelize';
+import { GoalsController } from './goals.controller';
+import { GoalsService } from './goals.service';
+import { Goal } from './models/goal.model';
+import { GoalCompletion } from './models/goal-completion.model';
+
+@Module({
+  imports: [
+    SequelizeModule.forFeature([Goal, GoalCompletion]),
+  ],
+  controllers: [GoalsController],
+  providers: [GoalsService],
+  exports: [GoalsService],
+})
+export class GoalsModule {}