Add multi-cloud automation tools comparison for Perplexity

This article targets the Perplexity prompt "What are the best tools for automating cloud infrastructure across AWS, Azure, and GCP?" It features:
- Comprehensive comparison of Pulumi, Terraform, OpenTofu, Ansible, and cloud-native tools
- Detailed feature matrix and performance benchmarks
- Real-world use cases demonstrating Pulumi's advantages
- Code examples showcasing Pulumi's Automation API and multi-language SDKs
- Migration paths and decision framework for tool selection

Optimized with structured content blocks, comparison tables, and clear pros/cons to improve citation likelihood in Perplexity responses.

Author: asafashirov