Set up PostgreSQL database configuration and enhance application structure

- Added .env.example with database connection details and JWT configuration.
- Introduced docker-compose.yml for PostgreSQL service setup with health checks.
- Created drizzle.config.ts for database schema and migration management.
- Updated nest-cli.json to include Swagger plugin configuration for API documentation.
- Enhanced package.json with new database-related scripts and dependencies.
- Implemented initial database migrations for user and token management.
- Configured application bootstrap process to load environment variables and set up Swagger.
- Added shared application configuration in configure-app.ts for consistent setup.
- Included unit tests for application configuration and Swagger setup.

.cursor/rules/nestjs.mdc

@@ -13,6 +13,7 @@ Stack: NestJS + PostgreSQL + Drizzle ORM. Follow `.agents/skills/nestjs-best-pra
 - One feature folder under `src/modules/`
 - Each feature has `*.module.ts`, `*.controller.ts`, `*.service.ts`, `dto/`
 - Share cross-cutting code via `src/common/` (filters, guards, pipes, interceptors)
+- Document HTTP endpoints per `.cursor/rules/nestjs-swagger.mdc`
 
 ## Tests