feat(v4): the system's UM*, UM/MOD, D+, DNEGATE, Q.* and Q./ call the ROM

MACHINE.md 2.2.  Each is its entry's address, push and ;.  Every node the
tests make carries the host ROM (host_load, Hera's births, the depth and
mesh tests' own nodes), and a division by zero inside the ROM returns to
the prompt (hosted-check).  test_host_quit's fetch outside memory moves
past the ROM's range: 16384 is the ROM's first word now the tests' system
has its ROM, as the product's always had.  dict_hash 0xfec8c47cfc6f437f.

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

v4/tests/test_host_depth.c

@@ -144,6 +144,7 @@ static unsigned starforth_node(unsigned k)
     int id = v4_fabric_add(&f, &pool[k], PORT);
     v4_node *n = &pool[k].n;
     memcpy(n->mem, nucleus.mem, sizeof n->mem);
+    v4_node_rom_attach(n, ROM_IMAGE, ROM_IMAGE_WORDS);   /* the nucleus calls its math in the ROM (MACHINE.md 2.2) */
     v4_node_stack_regs_attach(n, DSTACK_REG, RSTACK_REG);
     v4_node_error_attach(n, NODE_ERROR);
     v4_node_fault_attach(n, w_fault);