- CompletableDeferred.completeExceptionally(exception): fails the deferred
with a Lyng exception; the original exception object is preserved as
errorObject so assertThrows/catch see the correct class (works for both
built-in ObjException and user-declared class instances)
- LaunchPool: add maxQueueSize parameter (suspends launch when full),
add cancelAndJoin() for graceful shutdown that waits for running tasks,
clarify all semantics in the extern declaration comments
- Two tests for completeExceptionally (built-in and user-defined exception)
- Fix parallelism.md channel doc-test to be illustration-only (avoid
flakiness from coroutine scheduling in the doc-test runner)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
