feat(#131): back placement AM↔enfant + BDD garde/sans_garde

- API PATCH …/fiche, POST/DELETE …/enfants/:enfantId, GET avec amChildren
- Table enfants_assistantes_maternelles (option D, 1 garde active/enfant)
- Statuts enfant: garde/sans_garde remplacent actif (inscription → sans_garde)
- BDD.sql canonique réécrit; migration pour BDD existantes
- Seed test: hash bcrypt corrigé pour mot de passe « password »

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/src/entities/am_children.entity.ts

@@ -0,0 +1,47 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  ManyToOne,
+  JoinColumn,
+  CreateDateColumn,
+} from 'typeorm';
+import { AssistanteMaternelle } from './assistantes_maternelles.entity';
+import { Children } from './children.entity';
+import { Users } from './users.entity';
+
+@Entity('enfants_assistantes_maternelles', { schema: 'public' })
+export class AmChildren {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ name: 'id_am', type: 'uuid' })
+  amId: string;
+
+  @Column({ name: 'id_enfant', type: 'uuid' })
+  enfantId: string;
+
+  @Column({ name: 'date_debut', type: 'date' })
+  date_debut: Date;
+
+  @Column({ name: 'date_fin', type: 'date', nullable: true })
+  date_fin?: Date;
+
+  @CreateDateColumn({ name: 'cree_le', type: 'timestamptz' })
+  cree_le: Date;
+
+  @Column({ name: 'cree_par', type: 'uuid', nullable: true })
+  cree_par?: string;
+
+  @ManyToOne(() => AssistanteMaternelle, (am) => am.amChildren, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'id_am', referencedColumnName: 'user_id' })
+  am: AssistanteMaternelle;
+
+  @ManyToOne(() => Children, (c) => c.amLinks, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'id_enfant', referencedColumnName: 'id' })
+  child: Children;
+
+  @ManyToOne(() => Users, { nullable: true, onDelete: 'SET NULL' })
+  @JoinColumn({ name: 'cree_par', referencedColumnName: 'id' })
+  createdBy?: Users;
+}

backend/src/entities/assistantes_maternelles.entity.ts

@@ -1,5 +1,6 @@
-import { Entity, PrimaryColumn, Column, OneToOne, JoinColumn } from 'typeorm';
+import { Entity, PrimaryColumn, Column, OneToOne, OneToMany, JoinColumn } from 'typeorm';
 import { Users } from './users.entity';
+import { AmChildren } from './am_children.entity';
 
 @Entity('assistantes_maternelles')
 export class AssistanteMaternelle {
@@ -51,4 +52,7 @@ export class AssistanteMaternelle {
   /** Numéro de dossier (format AAAA-NNNNNN), même valeur que sur utilisateurs (ticket #103) */
   @Column({ name: 'numero_dossier', length: 20, nullable: true })
   numero_dossier?: string;
+
+  @OneToMany(() => AmChildren, (ac) => ac.am)
+  amChildren: AmChildren[];
 }

backend/src/entities/children.entity.ts

@@ -4,12 +4,14 @@ import {
 } from 'typeorm';
 import { Parents } from './parents.entity';
 import { ParentsChildren } from './parents_children.entity';
+import { AmChildren } from './am_children.entity';
 import { Dossier } from './dossiers.entity';
 
 export enum StatutEnfantType {
   A_NAITRE = 'a_naitre',
-  ACTIF = 'actif',
   SCOLARISE = 'scolarise',
+  GARDE = 'garde',
+  SANS_GARDE = 'sans_garde',
 }
 
 export enum GenreType {
@@ -68,6 +70,9 @@ export class Children {
   @OneToMany(() => ParentsChildren, pc => pc.child)
   parentLinks: ParentsChildren[];
 
+  @OneToMany(() => AmChildren, (ac) => ac.child)
+  amLinks: AmChildren[];
+
   // Relation avec Dossier
   @OneToMany(() => Dossier, d => d.child)
   dossiers: Dossier[];