Structured concurrency, fibers, parallel combinators, and execution scopes for fx.

First-class core.async channel bridging and stream combinators for fx.

High-level async coordination and synchronization primitives for fx:
Queues, Hubs, Deferreds, Semaphores, Latches, and Refs.

Fiber abstraction, supervisor tree, and concurrent execution runners for fx.

Core protocols for fibers, queues, coordination, and async communication in fx.