feat: Sprint 2 — moteur de combat PvE TetaRdPG

Moteur combat stateless (POST /api/combat/start résout le combat complet).
Formules GDD : Mêlée/Distance/Magie × 1.5, critique (5% + Chance×0.2%), esquive (5% + Chance×0.1%).
5 monstres seedés (Têtard Vase → Golem de Boue, level 1–9).
Level up : XP → seuil atteint → level++, +5 statPoints.
Persiste combat_logs (jsonb rounds). Validé : victoire, défaite, 401, 400, 404.

src/combat/combat.module.ts

@@ -0,0 +1,19 @@
+import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { Character } from '../character/entities/character.entity';
+import { CombatLog } from './combat-log.entity';
+import { CombatService } from './combat.service';
+import { CombatController } from './combat.controller';
+import { MonsterModule } from '../monster/monster.module';
+import { AuthModule } from '../auth/auth.module';
+
+@Module({
+  imports: [
+    TypeOrmModule.forFeature([Character, CombatLog]),
+    MonsterModule,
+    AuthModule,
+  ],
+  controllers: [CombatController],
+  providers: [CombatService],
+})
+export class CombatModule {}