feat: initialize monorepo structure with Bun and Turborepo

- Add package.json for the root with workspace configuration and scripts
- Create @gruperly/config package with TypeScript configuration
- Establish shared package @gruperly/shared with Zod schemas for validation
- Implement group, student, and payment schemas using Zod
- Set up TypeScript configuration for shared package
- Document stack architecture and technical specifications in stack.md
- Configure Turborepo with build, dev, lint, and typecheck tasks

README.md

@@ -1,2 +1,36 @@
-# gruperly
+# Gruperly
 
+Monorepo de Gruperly. Consulta [stack.md](./stack.md) para arquitectura y especificaciones.
+
+## Stack
+
+- Runtime & package manager: [Bun](https://bun.sh/)
+- Monorepo: Bun Workspaces + Turborepo
+- Backend (`apps/api`): Bun + Hono + Prisma + PostgreSQL + Better Auth
+- Frontend (`apps/web`): React 19 + TypeScript + TanStack Router + TanStack Query + Tailwind v4
+- Shared (`packages/shared`): esquemas Zod y tipos compartidos
+
+## Estructura
+
+```text
+apps/
+  api/      # Backend (Bun + Hono + Prisma)
+  web/      # Frontend (React PWA)
+packages/
+  shared/   # Esquemas Zod y tipos compartidos
+  config/   # tsconfig base compartido
+```
+
+## Comandos
+
+```bash
+bun install          # Instala dependencias de todos los workspaces
+bun run dev          # Levanta la API y la web (vía Turborepo)
+bun run db:push      # Aplica el esquema de Prisma a la base de datos
+bun run db:studio    # Abre Prisma Studio
+```
+
+## Setup de base de datos
+
+1. Crea una base PostgreSQL y copia `apps/api/.env.example` → `apps/api/.env`, ajustando `DATABASE_URL`.
+2. Ejecuta `bun run db:generate` y `bun run db:push` (o `bun run db:migrate` en desarrollo).