新增训练计划模块，包括控制器、服务、模型及数据传输对象，更新应用模块以引入新模块，同时在AI教练模块中添加体态评估功能，支持体重识别与更新，优化用户体重历史记录管理。

src/training-plans/training-plans.service.ts

@@ -0,0 +1,53 @@
+import { Injectable, NotFoundException } from '@nestjs/common';
+import { InjectModel } from '@nestjs/sequelize';
+import { TrainingPlan } from './models/training-plan.model';
+import { CreateTrainingPlanDto } from './dto/training-plan.dto';
+
+@Injectable()
+export class TrainingPlansService {
+  constructor(
+    @InjectModel(TrainingPlan)
+    private trainingPlanModel: typeof TrainingPlan,
+  ) { }
+
+  async create(userId: string, dto: CreateTrainingPlanDto) {
+    const id = `plan_${Date.now()}_${Math.random().toString(36).slice(2, 8)}`;
+    const createdAt = new Date();
+    const plan = await this.trainingPlanModel.create({
+      id,
+      userId,
+      createdAt,
+      startDate: new Date(dto.startDate),
+      mode: dto.mode,
+      daysOfWeek: dto.daysOfWeek,
+      sessionsPerWeek: dto.sessionsPerWeek,
+      goal: dto.goal,
+      startWeightKg: dto.startWeightKg ?? null,
+      preferredTimeOfDay: dto.preferredTimeOfDay ?? '',
+    });
+    return plan.toJSON();
+  }
+
+  async remove(userId: string, id: string) {
+    const count = await this.trainingPlanModel.destroy({ where: { id, userId } });
+    return { success: count > 0 };
+  }
+
+  async list(userId: string) {
+    const rows = await this.trainingPlanModel.findAll({ where: { userId }, order: [['created_at', 'DESC']] });
+    return rows.map(r => ({
+      id: r.id,
+      createdAt: r.createdAt,
+      startDate: r.startDate,
+      goal: r.goal,
+    }));
+  }
+
+  async detail(userId: string, id: string) {
+    const plan = await this.trainingPlanModel.findOne({ where: { id, userId } });
+    if (!plan) throw new NotFoundException('训练计划不存在');
+    return plan.toJSON();
+  }
+}
+
+