feat(v4.0.0): five nodes from nothing -- Hera asks for nodes, births and joins them

MESH.md step 5, in the fabric under test; the products are still one
node each until steps 8 and 9.

manage.c: what Hera asks of whoever holds the fabric, eleven requests by
KERNEL-WORD -- NODE-ME -BORN -WIRE -UNWIRE -SLEEP -WAKE -KILL -PARITY and
CAPSULE-OPEN -CELL -LINE. Nucleus: PORT!, SEND-ON, AWAIT, (SEAL).
capsules/v4/hera.4th: BIRTH and UNIT, the unit rule in FORTH and nowhere
else. The dictionary hash moves to the engine (v4_image_dict_hash).

test_host_unit.c, 34 checks, 64-bit: Hera is born empty, takes the
nucleus through her port, FORTH-79, POST and her capsule; 10 UNIT; four
nodes are born, each takes the nucleus and FORTH-79 through its port from
Hera and passes POST 538/538; four parities, one dictionary hash; they
talk, and a message between two corners not wired goes by Hera.

All v4 tests at both widths and under ASan+UBSan. hosted-check on three
ISAs. Bare metal: logs/20261006-143934 (amd64), -144204 (aarch64),
-144601 (riscv64).

Open, recorded in MESH.md: not run at 32 bits; a node that never answers
leaves Hera waiting; the capsules are read from files in the test, not
from the baked directory.

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

v4/capsule/core.v4

@@ -181,13 +181,18 @@ header CMOVE
   SET: (MQ-HEAD) a! !
   (MQ#) a! @  -1 +  ! ;
 
-\ ( port to -- )   take in a message.  B is at the port, by its address,
-\ and `to` is the message's first word, already read from it.  A length
+\ ( port to -- )   the seven words of a message being taken in, and the
+\ port, go into (MQ-HDR).  B is at the port, by its address, and `to` is
+\ the message's first word, already read from it.
+: (TAKE-HDR)
+  (MQ-HDR) a! !+  5 FOR @b !+ UNEXT  ! ;
+
+\ ( -- )   the message whose seven words are in (MQ-HDR) is kept with the
+\ messages waiting: its text is read from the port B is at.  A length
 \ below zero, or above what a message carries, is kept as -1 with no text:
 \ a longer one is read to its end first, so that what follows it is not
 \ taken for a message.
-: (TAKE)
-  (MQ-HDR) a! !+  5 FOR @b !+ UNEXT  !                                \ its seven words, and the port
+: (TAKE-KEEP)
   (MQ-HDR)+6 a! @  -if SIZED
   drop  -1 (MQ-HDR)+6 a! !  0  jump COUNTED
   SIZED: dup -1025 + -if LONG  drop  3 + 2/ 2/  jump COUNTED
@@ -203,6 +208,9 @@ header CMOVE
   GONE: drop
   LOSE: (LOST) a! @  1 +  ! ;
 
+\ ( port to -- )   take in a message and keep it
+: (TAKE)   (TAKE-HDR)  jump (TAKE-KEEP)
+
 \ ( port -- )   wait until a message may be begun on the port, by its
 \ address, taking in whatever is being written to this node meanwhile; and
 \ leave B at the port.  The port is kept in (GATE-PORT), not on the stack: