- A media-named FIFO or device node is refused before the open would
block on it (pre-open isFile check); POSIX FIFO regression test added.
- The full-body stream is bounded to the stat'ed size so concurrent
appends cannot exceed the declared Content-Length.
- Error responses carry no body for HEAD requests.
- Docs no longer overclaim the replacement race: the stat-identity
comparison narrows (does not fully close) the replacement window, and
the earlier realpath-to-stat window is acknowledged. Pairs re-recorded.