fix(08-05): route-cpu gate law re-anchored to the post-ALT measured truth (escalation record — no retirement)

Task 3, re-scoped per the plan's honest-FAIL branch: the CPU verdict FAILED
(the ladder ran to its documented stop), so the c3 class is NOT retired —
the record instead carries the executed-and-measured ALT truth.

- budget-gates.mjs: the verdict law documents the Phase-8 outcome (ALT
  EXECUTED, optimality green, CPU verdict FAIL 152.788/185.692 ms quoted
  with date; L=32 probe measured worse) — the stale 'next-milestone item'
  wording is gone; ROUTE_CPU_DRIFT_GUARD_MS re-anchored 200 → 400 (the
  post-ALT documented band outgrew the old guard; ≈2x the worst shipped-
  config run 185.692 ms); the guard stays a regression trip-wire, the 8 ms
  budget stays and its FAIL still prints every run
- budget-audit.test.mjs: CPU3 pins the new law (evidence must name the
  EXECUTED-in-Phase-8 verdict and must NEVER say 'next-milestone');
  19/19 vectors ok (the count holds — no vector dropped)
- docs/BUDGETS.md: route-cpu row carries the Phase-8 measured numbers +
  date; the c3 section is the honest post-ALT record (what changed, the
  quoted gate lines, the one-directional-Lipschitz wall, the open
  escalation) — staged as selective hunks; the tree's pre-existing
  doc-sync edits in other sections remain uncommitted, untouched

grep law: zero 'next-milestone' hits in budget-gates.mjs + BUDGETS.md;
ROUTE_CPU_DRIFT_GUARD_MS still exported and used.

scripts/test/budget-audit.test.mjs

@@ -111,6 +111,10 @@ await test("CPU3 on the current tree the ladder runs, the measured p95 is printe
   assert.match(r.evidence, /10 ms free-plan ceiling/, "the free-plan ceiling must be printed");
   assert.match(r.evidence, /GATE FAIL/, "the child's own GATE FAIL line (cross-metro class) is part of the evidence");
   assert.match(r.evidence, /c3/, "the accepted c3 escalation class must be named");
+  // 08-05 pin: the record carries the POST-ALT truth — the ALT lever was
+  // executed and measured over budget (never "a next-milestone item" again).
+  assert.match(r.evidence, /EXECUTED in Phase 8/, "the executed-and-measured ALT verdict must be named");
+  assert.doesNotMatch(r.evidence, /next-milestone/, "the stale next-milestone wording must never return");
 });
 
 await test("CPU4 a missing graph binary is notRun — NEVER a pass (T-07-22)", async () => {