feat: scaffold monorepo with Turborepo + NestJS + Next.js

- Turborepo monorepo with pnpm workspaces
- apps/api: NestJS 11.x with CQRS module
- apps/web: Next.js 14 App Router + TailwindCSS
- src/modules/shared: base entities, Result pattern, value objects
- TypeScript 5.7+ strict mode, shared tsconfig base
- Build pipeline: dev, build, lint, test, typecheck

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

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false