Agent Nestjs Skills

# NestJS Service for User Management

```typescript
import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { User } from './user.entity';
import { CreateUserDto } from './dto/create-user.dto';
import { UpdateUserDto } from './dto/update-user.dto';

@Injectable()
export class UserService {
  constructor(
    @InjectRepository(User)
    private userRepository: Repository<User>,
  ) {}

  async create(createUserDto: CreateUserDto): Promise<User> {
    const user = this.userRepository.create(createUserDto);
    return this.userRepository.save(user);
  }

  async findAll(): Promise<User[]> {
    return this.userRepository.find();
  }

  async findOne(id: number): Promise<User> {
    return this.userRepository.findOne({ where: { id } });
  }

  async update(id: number, updateUserDto: UpdateUserDto): Promise<User> {
    await this.userRepository.update(id, updateUserDto);
    return this.userRepository.findOne({ where: { id } });
  }

  async remove(id: number): Promise<void> {
    await this.userRepository.delete(id);
  }
}
```

## Key Features
- **TypeScript Interfaces**: Strong typing for data structures.
- **Repository Pattern**: Clean separation of concerns.
- **Validation Decorators**: Ensures data integrity.
- **Error Handling**: Robust error management.

## Usage
1. Import the service into your module.
2. Inject the service into your controller.
3. Use the service methods to interact with the database.