Vercel Services: Run full stack on Vercel

Introduces Vercel Services, a feature allowing multiple frameworks (frontend, backend, etc.) within a single Vercel Project. This enables atomic deployments, shared preview deployments, and internal service communication via service bindings. Configuration is done via `vercel.json`. Services can talk to each other internally without leaving Vercel's network. The post highlights zero-configuration deployment for various frameworks, integration with Fluid Compute and Active CPU pricing, Vercel Sandbox for isolated agent compute, WebSocket support, Vercel Connect for secure external access, Vercel Marketplace for databases, Vercel Queues/Workflows/Cron for background jobs, and Secure Compute/static IPs/VPC peering for private connections. Functions now support up to 30 minutes duration on Pro/Enterprise and 500MB dependency size for Python.