Initial commit: Plataforma de Economía

Features:
- React 18 + TypeScript frontend with Vite
- Go + Gin backend API
- PostgreSQL database
- JWT authentication with refresh tokens
- User management (admin panel)
- Docker containerization
- Progress tracking system
- 4 economic modules structure

Fixed:
- Login with username or email
- User creation without required email
- Database nullable timestamps
- API response field naming

.gitignore

@@ -0,0 +1,35 @@
+# Dependencies
+frontend/node_modules/
+backend/vendor/
+
+# Build outputs
+frontend/dist/
+backend/server
+
+# Environment files
+.env
+.env.local
+.env.*.local
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Logs
+*.log
+logs/
+
+# Test coverage
+coverage/
+*.cover
+
+# Temporary files
+tmp/
+temp/
+*.tmp