Description

This PR upgrades the NestJS example from v10 to v11 and modernizes the project configuration. The main changes include:

• NestJS Upgrade: Upgrade @nestjs/common, @nestjs/core, and @nestjs/platform-express from v10 to v11
• ESLint Migration: Migrate from legacy .eslintrc.js format to modern flat config format using eslint.config.mjs
• Configuration Cleanup: Remove legacy configuration files (.eslintrc.js, .prettierrc.js) and replace with modern equivalents
• Package Updates: Update dependencies and scripts across all packages in the monorepo
• Project Structure: Modernize the overall project structure with updated TypeScript and build configurations

Testing Instructions

1. Install Dependencies

   pnpm install
   pnpm build

2. Verify NestJS API

   pnpm --filter=api run dev

   • Check that the API starts without errors
   • Verify endpoints are accessible at http://localhost:3000

3. Test Web Application

   pnpm --filter=web run dev

   • Ensure the web app runs on http://localhost:3001
   • Verify the UI displays correctly

4. Linting and Formatting

   pnpm run lint
   pnpm run format

   • Confirm ESLint runs without errors
   • Verify Prettier formatting works correctly

5. Build Process

   pnpm build

   • Ensure all packages build successfully
   • Check for any TypeScript compilation errors

6. Run Tests

   pnpm test

   • Verify all tests pass
   • Check that Jest configuration works properly