fix(v4.0.0): step 6e final review -- texts begun in order; a word no one will read lets its writer go; a cut wire wakes a wait for room; a full console wire is a refusal, not a fault

The final review of step 6e, by a fresh reviewer told to break it, and
what was ruled: fix them all, test first.  Each has a test that failed
before the mend.

- Two texts from one node could be begun in the wrong order when room
  for their answers came between the node's look at the first and at the
  second.  Texts whose answers go by the same port are begun in the order
  they came: (D-MASK), quit.v4.  102 of 700 timings were wrong before.
- A word written with PORT! to a node that speaks whole messages, or to
  a console's port, blocked its writer for ever and cut off every node
  beyond it.  It is error 18 now, whether that node is asleep, running
  or stuck: fabric.c, node.c.
- A node asleep for room on one wire is woken when another of its wires
  is cut.
- A line there was no room for on the lone node's wire was reported as a
  fault and ended the hosted program.  It is Message refused, and the
  prompt comes back: V4_BOOT_LINE_REFUSED.  hosted-check has the case;
  no bare-metal boot has typed it.
- Ruled: text behind held output for the same port is refused though it
  would fit.  MESH.md 7d.4 said otherwise and is corrected.
- The removal test also cuts and re-makes a wire, and has an exchange in
  which output is held at a full wire: 26,814 disturbances in all.
- MESH.md and v4/README.md no longer say that a stuck node holds up no
  other node, that only printing waits, or that no node is left waiting
  on one that is gone; 7d.6 lists the limits and what the products do
  that they did not before.

make -C v4 test and sanitize at both widths, hosted-check, lint.  Three
bare-metal boots: logs/20261013-194827 (amd64), -195131 (aarch64),
-195518 (riscv64).  POST 538 of 538, word_count=317,
dict_hash=0xe5a57f3eb72ff94a on all six; the three sessions are the same
character for character.  The boots were built with the working tree's
uncommitted change to kernel/Makefile that adds the ISA to the kernel's
version line.

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

v4/capsule/quit.v4

@@ -105,6 +105,14 @@ macro R-CLEAR   RSTACK-DEPTH b! a !b   endmacro
 \             whose answers go different ways, and each is begun when
 \             its own has the room.  That room is kept from then until
 \             the answer has gone.
+\             TEXTS WHOSE ANSWERS GO THE SAME WAY ARE BEGUN IN THE ORDER
+\             THEY CAME.  Once one has been left for want of room, every
+\             text behind it on this pass whose answer goes by that port
+\             is left too, though the room has come since: (D-MASK) has
+\             a bit for each such port.  (As first built only the room
+\             was asked, each time; room that came between the look at
+\             one text and at the next began the second first.  Found
+\             by the final review of step 6e.)
 \   a NACK    is taken and counted in (REFUSED)
 \   a GONE    is taken, and believed if this node's centre sent it
 \   an answer no one is waiting for is dropped: a SEND that is not waited
@@ -128,7 +136,7 @@ macro R-CLEAR   RSTACK-DEPTH b! a !b   endmacro
 \ for no one.
 : (IDLE)
   L: 1 (QUIET) a! !                                                   \ nothing here is any text's doing: see (RAISED)
-  -1 (KEEP) a! !  0 (AWAIT-FROM) a! !  -1 (DEFER) a! !
+  -1 (KEEP) a! !  0 (AWAIT-FROM) a! !  -1 (DEFER) a! !  0 (D-MASK) a! !
   (SERVE)  (MINE0)
   M: (MINE) if REST
      drop  (IN)+2 a! @  -1 + if TEXT  -3 + if NACK  -1 + if GONE
@@ -145,10 +153,15 @@ macro R-CLEAR   RSTACK-DEPTH b! a !b   endmacro
      TEXT: drop
      (IN)+1 a! @ (WAY)  -if T1  drop  (S-WIRE) a! @                   \ the way back; with none known, the wire it came on
      T1: (DONE-PORT) a! !
+     (DONE-PORT) a! @ (WBIT)  (D-MASK) a! @  and if FREE1  jump FULL  \ text ahead of it waits for room on that wire
+     FREE1: drop
      8  (DONE-PORT) a! @  (ROOM?)  if START  -1 + if FULL
      drop  (S-WIRE) a! @ (DONE-PORT) a! !                             \ no one is on that port: back by the wire it came on,
+     (S-WIRE) a! @ (WBIT)  (D-MASK) a! @  and if FREE2  jump FULL
+     FREE2: drop
      8  (S-WIRE) a! @  (ROOM?)  -1 + if FULL  jump START              \   if that has the room -- or has no one on it either
-     FULL: drop  (DEFER) a! @  -if LATER  drop  (DONE-PORT) a! @  (DEFER) a! !  (SKIP)  jump M
+     FULL: drop  (DONE-PORT) a! @ (WBIT)  dup inv  (D-MASK) a! @  and  +  !
+     (DEFER) a! @  -if LATER  drop  (DONE-PORT) a! @  (DEFER) a! !  (SKIP)  jump M
      LATER: drop  (SKIP)  jump M
   REST: drop
      (DEFER) a! @  -if ROOM  drop  (SLEEP)  jump L