feat: Intégration du backend NestJS depuis YNOV

- Framework: NestJS avec TypeORM
- Authentification: JWT (access + refresh tokens)
- Gestion utilisateurs: CRUD complet avec validation
- Routes: auth, users, parents, assistantes maternelles
- Dockerfile pour conteneurisation

backend/src/routes/parents/parents.service.ts

@@ -0,0 +1,74 @@
+import {
+  BadRequestException,
+  ConflictException,
+  Injectable,
+  NotFoundException,
+} from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+import { Parents } from 'src/entities/parents.entity';
+import { RoleType, Users } from 'src/entities/users.entity';
+import { CreateParentDto } from '../user/dto/create_parent.dto';
+import { UpdateParentsDto } from '../user/dto/update_parent.dto';
+
+@Injectable()
+export class ParentsService {
+  constructor(
+    @InjectRepository(Parents)
+    private readonly parentsRepository: Repository<Parents>,
+    @InjectRepository(Users)
+    private readonly usersRepository: Repository<Users>,
+  ) {}
+
+  // Création d’un parent
+  async create(dto: CreateParentDto): Promise<Parents> {
+    const user = await this.usersRepository.findOneBy({ id: dto.user_id });
+    if (!user) throw new NotFoundException('Utilisateur introuvable');
+    if (user.role !== RoleType.PARENT) {
+      throw new BadRequestException('Accès réservé aux parents');
+    }
+
+    const exist = await this.parentsRepository.findOneBy({ user_id: dto.user_id });
+    if (exist) throw new ConflictException('Ce parent existe déjà');
+
+    let co_parent: Users | null = null;
+    if (dto.co_parent_id) {
+      co_parent = await this.usersRepository.findOneBy({ id: dto.co_parent_id });
+      if (!co_parent) throw new NotFoundException('Co-parent introuvable');
+      if (co_parent.role !== RoleType.PARENT) {
+        throw new BadRequestException('Accès réservé aux parents');
+      }
+    }
+
+    const entity = this.parentsRepository.create({
+      user_id: dto.user_id,
+      user,
+      co_parent: co_parent ?? undefined,
+    });
+
+    return this.parentsRepository.save(entity);
+  }
+
+  // Liste des parents
+  async findAll(): Promise<Parents[]> {
+    return this.parentsRepository.find({
+      relations: ['user', 'co_parent', 'parentChildren', 'dossiers'],
+    });
+  }
+
+  // Récupérer un parent par user_id
+  async findOne(user_id: string): Promise<Parents> {
+    const parent = await this.parentsRepository.findOne({
+      where: { user_id },
+      relations: ['user', 'co_parent', 'parentChildren', 'dossiers'],
+    });
+    if (!parent) throw new NotFoundException('Parent introuvable');
+    return parent;
+  }
+
+  // Mise à jour
+  async update(id: string, dto: UpdateParentsDto): Promise<Parents> {
+    await this.parentsRepository.update(id, dto);
+    return this.findOne(id);
+  }
+}