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/entities/assistantes_maternelles.entity.ts

@@ -0,0 +1,51 @@
+import { Entity, PrimaryColumn, Column, OneToOne, JoinColumn } from 'typeorm';
+import { Users } from './users.entity';
+
+@Entity('assistantes_maternelles')
+export class AssistanteMaternelle {
+  // PK = FK vers utilisateurs.id
+  @PrimaryColumn('uuid', { name: 'id_utilisateur' })
+  user_id: string;
+
+  @OneToOne(() => Users, (user) => user.assistanteMaternelle, {
+    onDelete: 'CASCADE',
+  })
+  @JoinColumn({ name: 'id_utilisateur', referencedColumnName: 'id' })
+  user: Users;
+
+  @Column({ name: 'numero_agrement', length: 50, nullable: true })
+  approval_number?: string;
+
+  @Column({ name: 'nir_chiffre', length: 15, nullable: true })
+  nir?: string;
+
+  @Column({ name: 'nb_max_enfants', type: 'int', nullable: true })
+  max_children?: number;
+
+  @Column({ name: 'biographie', type: 'text', nullable: true })
+  biography?: string;
+
+  @Column({
+    name: 'disponible',
+    type: 'boolean',
+    default: true,
+    nullable: true,
+  })
+  available?: boolean;
+
+  @Column({ name: 'ville_residence', length: 100, nullable: true })
+  residence_city?: string;
+
+  @Column( { name: 'date_agrement', type: 'date', nullable: true })
+  agreement_date?: Date;
+
+  @Column( { name: 'annee_experience', type: 'smallint', nullable: true })
+  years_experience?: number;
+  
+  @Column( { name: 'specialite', length: 100, nullable: true })
+  specialty?: string;
+
+  @Column( { name: 'place_disponible', type: 'integer', nullable: true })
+  places_available?: number;
+
+}