feat(sprint-5.5): add NestJS API, BlockMetaBar, block components + fix Vercel build

- Add vercel.json to build only apps/web (fix Vercel build failure)
- NestJS API: BlocksModule, BlocksController, BlocksService with Prisma 7
- PostgreSQL migration: Block model (path, version, isInPreview)
- BlockMetaBar component: inline version edit, API fetch with offline fallback
- New block components: CeoBlock, ContactFormsBlock, FooterBlock, NewsBlock, ReviewsBlock
- PreviewClient: fetch isInPreview from API, block visibility toggle
- Pages updated: hero, doctors, ceo, contact-forms, contact, news, reviews
- docker-compose: PostgreSQL on port 5434

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/src/main.ts

@@ -1,8 +1,10 @@
+import 'dotenv/config';
 import { NestFactory } from '@nestjs/core';
 import { AppModule } from './app.module';
 
 async function bootstrap() {
   const app = await NestFactory.create(AppModule);
+  app.enableCors({ origin: 'http://localhost:3001' });
   await app.listen(process.env.PORT ?? 3000);
 }
 bootstrap();