Re-introducing the Cloudflare Workers Playground

Introduced a revamped Cloudflare Workers Playground with a new VSCode-powered editor supporting multi-module Workers, type-checking, and real-time previews. Enhanced developer tooling with Chrome DevTools integration for logs, network requests, and profiling. Added the ability to share and deploy playground code directly to Cloudflare's global network, focusing on the Worker-as-origin use-case.