feat(v4): word accounts at call -- the word ID in the header, the kernel's records, the Stadium charged per tick (#189)

ENGINE step 4 Phase 2 (plan docs/v4.0.0/plans/2026-11-13-engine-step4-phase2-word-accounts.md). Rulings,
Captain Bob 2026-11-13: "ID field in the header"; "Per heartbeat tick"; the ACL "All of it in Phase 4".

- The word ID, at xt-4 before the flags (ENGINE.md 3b). The system's words are numbered as they are
  assembled, by a new directive, #id, (and #ids, the count), in the C assembler (text.c) and in the
  machine ROM's (capsules/v4/rom), which counts in the system's own (NEXT-ID). (HEADER) numbers later
  words; FORGET gives back the IDs it frees, always the newest; COLD resets to (BOOT-ID); (SEAL) records
  it. All 313 system headers carry the cell.
- The kernel's records (v4/mesh.h): (TELL-DEFINED) and (TELL-FORGOTTEN), requests -19/-20 on port 0,
  which the kernel puts in (WORD-DEFINED)/(WORD-FORGOTTEN) when it seals a node, and reads the system's
  own words once. A bit per address marks a word's xt (calls into the ROM or headerless code are not
  words); at call, the bit test and a count. v4_mesh_charge hands the owner the calls since.
- The Stadium: stadium_words_charge -- N calls as N of stadium_word_dispatch's dispatches, shared by calls
  when the reservoir is short; sk_v4.c charges every node's words at the tick beside its opcodes, and
  stadium_word_forget before an ID is used again.
- Tests first: test_text.c, test_host_dict.c, test_host_quit.c (numbering, FORGET, COLD),
  test_mesh_boot.c (44 checks), kernel/tests/test_stadium_words.c; qemu_session.py: Hera's words
  admitted after POST.
- amd64: Stadium words: promotions=141 after POST, CONSERVED; POST 539/539; word_count=377;
  dict_hash 0xa854ba15b437d288 (the new cell); the boot 142 s against Phase 1's 153 s.
- v4 test, test-32: all pass; v4-checks: 80 programs under the sanitizers, 0 failures; the hosted
  builds alike. docs/reference/v4-dictionary.tsv: the two new words; FABRIC-3 XLVIII.24.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017RzZgrf7V7Zk2iczBXDRbm

scripts/qemu_session.py

@@ -485,6 +485,10 @@ def physics():
     check("the Stadium: its cells allocated", re.search(r"Stadium: \d+ cells", text()) is not None)
     check("the Stadium: conservation CONSERVED", wait_for(r"Stadium conservation: CONSERVED", 120))
     check("the heartbeat: ticking", wait_for(r"Heartbeat: [1-9]\d* ticks", 120))
+    # Phase 2 (#189): Hera's words are in the Stadium -- every call to a word counted on the kernel's record
+    # of it, joined by the word ID in its header, and charged after POST (Captain Bob, 2026-11-13)
+    check("the Stadium: Hera's words admitted after POST",
+          re.search(r"Stadium words: promotions=[1-9]\d*", text()) is not None)
 
 
 def registry():