add JWT_SECRET fallback, remove env_file from compose

backend/src/auth/auth.module.ts

@@ -13,7 +13,7 @@ import { JwtStrategy } from './jwt.strategy';
       imports: [ConfigModule],
       inject: [ConfigService],
       useFactory: (config: ConfigService) => ({
-        secret: config.get<string>('JWT_SECRET'),
+        secret: config.get<string>('JWT_SECRET') || 'dev-secret',
         signOptions: { expiresIn: '7d' },
       }),
     }),

backend/src/auth/jwt.strategy.ts

@@ -13,7 +13,7 @@ export class JwtStrategy extends PassportStrategy(Strategy) {
     super({
       jwtFromRequest: ExtractJwt.fromAuthHeaderAsBearerToken(),
       ignoreExpiration: false,
-      secretOrKey: config.get<string>('JWT_SECRET')!,
+      secretOrKey: config.get<string>('JWT_SECRET') || 'dev-secret',
     });
   }