Applications can run isolated worker pools across CPU cores

Add first-class Worker projects and a WorkerPool API so Desktop and Command Line applications can queue CPU-intensive jobs to isolated child processes that run concurrently across the machine's available processor cores. Studio should compile, run, debug, build, publish, and deploy referenced workers automatically. Jobs need binary and text payloads, progress reporting, cooperative cancellation with forced termination fallback, structured failures, bounded queues, configurable process counts and priorities, and crash isolation/recovery.