🎓 Initial commit: Math2 Platform - Plataforma de Álgebra Lineal PRO

✨ Características:
- 45 ejercicios universitarios (Basic → Advanced)
- Renderizado LaTeX profesional
- IA generativa (Z.ai/DashScope)
- Docker 9 servicios
- Tests 123/123 pasando
- Seguridad enterprise (JWT, XSS, Rate limiting)

🐳 Infraestructura:
- Next.js 14 + Node.js 20
- PostgreSQL 15 + Redis 7
- Docker Compose completo
- Nginx + SSL ready

📚 Documentación:
- 5 informes técnicos completos
- README profesional
- Scripts de deployment automatizados

Estado: Producción lista ✅

.github/PULL_REQUEST_TEMPLATE.md

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+## Description
+
+<!-- Provide a brief description of the changes in this PR -->
+
+## Type of Change
+
+- [ ] Bug fix (non-breaking change which fixes an issue)
+- [ ] New feature (non-breaking change which adds functionality)
+- [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
+- [ ] Documentation update
+- [ ] Refactoring (no functional changes)
+- [ ] Performance improvement
+- [ ] Test coverage improvement
+- [ ] Security fix
+
+## Related Issues
+
+<!-- Link to related issues using "Fixes #123" or "Relates to #456" -->
+Fixes #
+Relates to #
+
+## Changes Made
+
+<!-- Describe the changes in detail -->
+- Change 1
+- Change 2
+- Change 3
+
+## Testing
+
+<!-- Describe the tests you ran and how to reproduce them -->
+- [ ] Unit tests pass
+- [ ] Integration tests pass
+- [ ] E2E tests pass
+- [ ] Manual testing completed
+
+### Test Instructions
+
+1. Step one
+2. Step two
+3. Step three
+
+## Screenshots (if applicable)
+
+<!-- Add screenshots for UI changes -->
+
+## Checklist
+
+- [ ] My code follows the project's style guidelines
+- [ ] I have performed a self-review of my code
+- [ ] I have commented my code, particularly in hard-to-understand areas
+- [ ] I have made corresponding changes to the documentation
+- [ ] My changes generate no new warnings
+- [ ] I have added tests that prove my fix is effective or that my feature works
+- [ ] New and existing unit tests pass locally with my changes
+- [ ] Any dependent changes have been merged and published
+
+## Security Considerations
+
+- [ ] No secrets or credentials exposed
+- [ ] Input validation implemented
+- [ ] Authorization checks added
+- [ ] Security implications considered
+
+## Breaking Changes
+
+<!-- If this is a breaking change, describe what breaks and how to migrate -->
+
+## Additional Notes
+
+<!-- Any additional information that reviewers should know -->