feat: Sprint 1 — backend fondations TetaRdPG

Auth SuperOAuth (JWT validation + httpOnly cookie), entités users/characters/level_thresholds,
lazy calculation endurance, seed 100 niveaux, config prod-ready (trust proxy, helmet, CORS, rate limit).
Validé : health 200, auth flow, character CRUD, endurance lazy, 401 sans cookie.

src/character/entities/character.entity.ts

@@ -0,0 +1,75 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  ManyToOne,
+  JoinColumn,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Unique,
+} from 'typeorm';
+import { User } from '../../user/user.entity';
+
+@Entity('characters')
+@Unique(['userId'])
+export class Character {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ name: 'user_id' })
+  userId: string;
+
+  @ManyToOne(() => User)
+  @JoinColumn({ name: 'user_id' })
+  user: User;
+
+  @Column({ length: 100 })
+  name: string;
+
+  @Column({ default: 1 })
+  level: number;
+
+  @Column({ default: 0 })
+  xp: number;
+
+  @Column({ default: 0 })
+  gold: number;
+
+  // Stats (cap : 101)
+  @Column({ default: 1 })
+  force: number;
+
+  @Column({ default: 1 })
+  agilite: number;
+
+  @Column({ default: 1 })
+  intelligence: number;
+
+  @Column({ default: 1 })
+  chance: number;
+
+  @Column({ default: 1 })
+  vitalite: number;
+
+  @Column({ name: 'hp_current', default: 100 })
+  hpCurrent: number;
+
+  @Column({ name: 'hp_max', default: 100 })
+  hpMax: number;
+
+  // Endurance — lazy calculation (pas de timer actif)
+  @Column({ name: 'endurance_saved', default: 100 })
+  enduranceSaved: number;
+
+  @Column({ name: 'last_endurance_ts', type: 'timestamp', default: () => 'NOW()' })
+  lastEnduranceTs: Date;
+
+  @Column({ name: 'endurance_max', default: 100 })
+  enduranceMax: number;
+
+  @CreateDateColumn({ name: 'created_at' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at' })
+  updatedAt: Date;
+}