feat(documents): full regional doc set (front/back + criminal record) + CS data-entry + DB pool bump

- doc types with side (front/back/single): license, national_id, vehicle_registration (both sides), criminal_record, selfie, vehicle_photo
- fields: side, holder_name(encrypted), issue_date, extra jsonb; REQUIRED_DOCS checklist + /requirements
- CS/admin: POST /admin/drivers/:id/documents (upload for driver), list, review auto-approves when complete
- face-match endpoint stub (Gemini/Face provider later)
- DB pool extra.max=30 (raises concurrency ceiling); migration DocumentsFields

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/src/app.module.ts

@@ -41,6 +41,8 @@ import { DocumentsModule } from './modules/documents/documents.module';
         database: cfg.get<string>('db.name'),
         username: cfg.get<string>('db.user'),
         password: cfg.get<string>('db.password'),
+        // بركة اتصالات أكبر — يرفع سقف التزامن تحت الحمل العالي
+        extra: { max: parseInt(process.env.DB_POOL_MAX ?? '30', 10) },
         // بادئة الجداول (tripz_) لعزل السيرفر المشترك — راجع docs/14
         entityPrefix: cfg.get<string>('db.tablePrefix'),
         synchronize: cfg.get<boolean>('db.synchronize'),