fix(v4.0.0): what a node passes on waits with it, offered -- a relay is not held by a stuck node

Found after the last commit: a message being passed on toward a node that
was stuck held the node passing it on in the wait, taking in what came
but serving none of it; text typed for a stuck node left Hera deaf.  And
a node that had done text for a sender that then stuck waited on it to
give its answer.

A node with nothing to do now deals first with what is for itself; then
offers at once the first message for each port and each refusal owed,
and sleeps in the wait.  What is taken is written and done with; the
rest stays with the messages waiting, in order.  How text ended is put
with the messages waiting, not written from (FINISH).  The stack is kept
as shallow between lines as it was.

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

v4/tests/test_host_quit.c

@@ -63,7 +63,7 @@ static v4_heat       h;
 static v4_text       tx;
 static v4_cell       w_key, w_key_end, w_fault, capsule_latest;
 static v4_cell       w_idle;             /* (IDLE): where the node waits for a message */
-static v4_cell       w_idle_end;         /* (PASS-ON): the word after it */
+static v4_cell       w_idle_end;         /* (LINE): the word after it */
 static char          out[V4_CONSOLE_CAP + 1];
 
 /* STORAGE (MESH.md section 8).  The node asks its kernel for its blocks, and
@@ -871,7 +871,7 @@ int main(void)
     printf("  capsule: %ld words\n", (long)v4_text_here(&tx) - 16);
     if (failures) { printf("  %d checks, %d failures\n", checks, failures); return 1; }
     w_idle = v4_text_word(&tx, "(IDLE)");
-    w_idle_end = v4_text_word(&tx, "(PASS-ON)");       /* the word after (IDLE) in quit.v4 */
+    w_idle_end = v4_text_word(&tx, "(LINE)");          /* the word after (IDLE) in quit.v4 */
     w_key = v4_text_word(&tx, "KEY");
     w_key_end = v4_text_word(&tx, "CR");               /* the word after KEY in core.v4 */
     w_fault = v4_text_word(&tx, "(FAULTS)");