feat(v4.0.0): refusals and waits on bare metal, and step 6c written up

The bare-metal host hands a waiting node the next line typed, as the
hosted one does: 5 AWAIT, then 7 8 * . -- Interrupted, then 56.

amd64, aarch64 and riscv64 boot, POST 538 of 538, word_count=317,
dict_hash 0x54520ade672566ad, the same as the three hosted programs:
logs/20261007-202737, -203230, -203616.

MESH.md step 6c: what was built, how it was verified, and two things
found on the way that are not mended and are for ruling: Hera blocked
writing to a stuck node, and a message that can go round for ever between
two nodes whose ways disagree.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/v4.0.0/MESH.md

@@ -136,9 +136,8 @@ word address `base`:
   three boots type `5 7 PORT!` and go on: `logs/20261007-121743` (amd64),
   `-122008` (aarch64), `-122337` (riscv64); POST 538 of 538,
   `dict_hash=0x5f0a949a6fc8ef2b` on all six.
-  **Not mended, and reported:** a node that waits at "any port" for an
-  answer that never comes (`AWAIT`, on a node that never answers) waits
-  for ever, and on the lone node that ends the line as "stopped".
+  A node that waited at "any port" for an answer that never came
+  (`AWAIT`) was not mended by this, and was by step 6c: section 7b.
 
 ### 4.2 A node at reset
 
@@ -921,8 +920,40 @@ Each is tested, committed and pushed before the next.
    6. *The suite.* `make -C v4 test` and `sanitize` pass at both widths;
       `mkcapsule --lint capsules/` is clean.
 
-   **6c. Refusals and waits (section 7b).** Acceptance, approved
-   2026-10-07:
+   **6c. Refusals and waits (section 7b).** **Done 2026-10-07.**
+   - *In the nucleus* (`v4/capsule/core.v4`, `quit.v4`): `(OWE)` and
+     `(PAY)`; the room kept for NACK and GONE; `NO-ROUTE`; `GONE`; `AWAIT`
+     ending in errors 19, 20 and 21; `(REFUSED)`.
+   - *Hera* (`capsules/v4/hera.4th`): her table of the nodes she has had
+     born, and `KILL`.
+   - *The lone node* (`v4/system/boot.c`, `v4/tools/hosted.c`,
+     `kernel/src/v4/sk_v4.c`): a line that waits is reported as waiting,
+     and the next line typed breaks the wait and is then done.
+   - *Tests.* `v4/tests/test_host_mesh.c`, 76 checks, three nodes in a row:
+     acceptance 1, 2 and 7, a GONE from a node's centre and one that is
+     not, and a console line breaking a wait while text for another node
+     passes through. `v4/tests/test_host_unit.c`, 74 checks: acceptance 3,
+     4 and 5, and `KILL` of what is not a node of hers. `hosted-check` and
+     the three boots type `5 AWAIT` and then another line: acceptance 6.
+   - *Verified.* `make -C v4 test`, `sanitize` and `hosted-check`; three
+     bare-metal boots, `logs/20261007-202737` (amd64), `-203230`
+     (aarch64), `-203616` (riscv64). On all six: POST 538 of 538,
+     `word_count=317`, `dict_hash=0x54520ade672566ad`.
+   - **Found on the way, and not mended: for ruling.**
+     - *Hera blocked writing to a stuck node.* Hera has the lowest number,
+       so by section 7a she writes to a neighbour without looking and is
+       blocked until it reads. If that neighbour is stuck she is blocked
+       writing, not waiting, and a line from the console does not release
+       her. `KILL` sends GONE to every other node, so with two nodes stuck
+       at once, killing one would leave her blocked on the other.
+     - *A message that goes round for ever.* When a node forgets the way to
+       another, what it sends there goes by its way for everything else.
+       If the node at that end still believes the way is back through the
+       first, the message passes between them without end: nothing counts
+       hops (the TTL is carried and not acted on). `KILL` has Hera forget
+       her own way first, which prevents it there.
+
+   Acceptance, approved 2026-10-07:
    1. *No room.* A node's queue is filled; the next message for it is
       refused, and the sender's `(REFUSED)` count rises by one. A sender
       that was waiting has its line end "Message refused".