Addresses the review's two carried warnings and the comment suggestion:
- Once the ledger truncates, every arm that marks it (admit()'s two ceilings and
the child-marker frame arm) now clears both stray pipes' buffered output
wholesale, so the end-path flushStray sees empty buffers instead of
concat+decoding doomed data near a 256 MiB maxLogBytes; captureStray's newline
loop re-checks the flag before re-retaining the residual.
- The child runs with -u (unbuffered), so sys.__stdout__/sys.__stderr__ writes
are visible to stray capture immediately; the settlement flush still drains
the original std streams before the done frame as a guard. A regression test
writes through sys.__stdout__/sys.__stderr__ without an explicit flush and
asserts both bytes land in logs. C-ext stdio remains an accepted residual,
recorded in the README Known Limitations (en + zh).
- The ledger-comment arithmetic now states the exact boundary (serializes to
exactly maxLogBytes; without the reserved byte it would be maxLogBytes + 1)
in both host and child.
Note (en + zh) registers the stray-clear and -u/settlement-drain mechanisms and
the new test; pairings re-recorded; corpus passes 1029.