The review of step 6c found it did not keep its rule. Ruled: fix them
all; 16 hops.
- Paying a NACK no longer waits on a lower-numbered neighbour; a node
that owes one does not sleep, and goes on taking in what it is sent.
- AWAIT looks first through the messages already waiting.
- A node waiting to write to a removed neighbour gets error 18: the
word that says who is reading also says which ports have anything on
them.
- A console line lets Hera go when she is blocked on the first word of
a message (v4_fabric_interrupt_error, a device's `pending`).
- A refused answer is told to the node that waits, not the one that
answered; one owed to the node itself goes to its own queue.
- A message is passed on by at most 16 nodes, then refused.
- A GONE is believed only when it says it is from the node's centre.
- Tests: the check that tested nothing is replaced; no room for a
waiting sender; the limit that remains is tested as a limit.
- MESH.md 7b's rule reworded to what holds, 7b.7 says where it falls
short; README likewise.
make -C v4 test, sanitize, hosted-check; three bare-metal boots. POST
538 of 538, word_count=317, dict_hash=0xc0769523a47b7dc3 on all six.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
