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/contrats.entity.ts

@@ -0,0 +1,57 @@
+import { Column, CreateDateColumn, Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn, UpdateDateColumn } from "typeorm";
+import { Dossier } from "./dossiers.entity";
+
+export enum StatutContratType {
+  BROUILLON = 'brouillon',
+  EN_ATTENTE_SIGNATURE = 'en_attente_signature',
+  VALIDE = 'valide',
+  RESILIE = 'resilie',
+}
+
+@Entity('contrats')
+export class Contrat {
+  // Define your columns and relationships here
+
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @OneToOne(() => Dossier, {onDelete: 'CASCADE'} )
+  @JoinColumn({ name: 'id_dossier'})
+  dossier: Dossier;
+
+  @Column({type: 'jsonb', nullable: true, name: 'planning'})
+  planning?: any;
+
+  @Column({type: 'numeric', precision: 6, scale: 2, nullable: true, name: 'tarif_horaire'})
+  hourly_rate?: string;
+
+  @Column({type: 'numeric', precision: 6, scale: 2, nullable: true, name: 'indemnites_repas'})
+  meal_indemnity?: string;
+
+  @Column( { name: 'date_debut', type: 'date', nullable: true })
+  start_date?: Date;
+
+  @Column({
+    type: 'enum',
+    enum: StatutContratType,
+    enumName: 'statut_contrat_type',
+    default: StatutContratType.BROUILLON,
+    name: 'statut'
+  })
+  statut: StatutContratType;
+
+  @Column({type: 'boolean', default: false, name: 'signe_parent'})
+  signed_by_parent: boolean;
+
+  @Column({type: 'boolean', default: false, name: 'signe_am'})
+  signed_by_am: boolean;
+
+  @Column({type: 'timestamptz', nullable: true, name: 'finalise_le'})
+  finalized_at?: Date;
+
+  @CreateDateColumn({ name: 'cree_le', type: 'timestamptz' })
+  created_at: Date;
+
+  @UpdateDateColumn({ name: 'modifie_le', type: 'timestamptz' })
+  updated_at: Date;
+}