feat(shared): add shared module with domain primitives, infrastructure services, and utils

Domain primitives: BaseEntity, AggregateRoot, ValueObject, DomainEvent, Result<T,E>
Infrastructure: PrismaService, RedisService, LoggerService (pino), EventBusService
Utils: Vietnam phone validator/normalizer, VND currency formatter, Vietnamese slug generator
Includes 45 unit tests covering all domain primitives, validators, and formatters.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/api/src/modules/shared/shared.module.ts

@@ -0,0 +1,14 @@
+import { Global, Module } from '@nestjs/common';
+import { EventEmitterModule } from '@nestjs/event-emitter';
+import { EventBusService } from './infrastructure/event-bus.service';
+import { LoggerService } from './infrastructure/logger.service';
+import { PrismaService } from './infrastructure/prisma.service';
+import { RedisService } from './infrastructure/redis.service';
+
+@Global()
+@Module({
+  imports: [EventEmitterModule.forRoot()],
+  providers: [PrismaService, RedisService, LoggerService, EventBusService],
+  exports: [PrismaService, RedisService, LoggerService, EventBusService],
+})
+export class SharedModule {}