feat(08.1-02): re-pin measurement gates for ARG3 and extend the rollout locks (GREEN)

- The optimality gate's decode-failure message names ARG3 and the rebuild
  command (node routing/scripts/build-road-graph.mjs); the frozen D-03
  constants (OPTIMALITY_EPSILON_PCT = 0.1, REQUIRED_BASELINE_ARG_VERSION
  = 1) and the immutable alt-baseline.json record are untouched.
- The oracle sweep's graph-missing (SKIP) and decode-failure wording names
  the ARG3 binary; the seeded 200-pair symmetric-compare constants and the
  three violation classes are unchanged.
- RO1/RO2 ban the ARG3 magic 0x41524733 in the upload script's and the
  Worker's comment-stripped code: the one-path laws now cover the CURRENT
  format, not just the retired ones. The Worker keeps exactly one
  decodeGraph call, no GRAPH_VERSION, no magic, no === 2.
- measure-route-cpu.mjs is untouched here by design: its LADDER HISTORY
  gains the CH rung only once the measured numbers exist (task 3).

routing/scripts/measure-optimality-gate.mjs

@@ -23,8 +23,9 @@
  * Inputs:
  *   - the COMMITTED record  routing/test/fixtures/alt-baseline.json (IMMUTABLE
  *     — the recorder refuses overwrite; delete by explicit git revert only);
- *   - the LOCAL rebuilt binary routing/data/kl-roadgraph.v1.bin (ARG2 — the
- *     storage NAME stays v1; the header version is the format truth).
+ *   - the LOCAL rebuilt binary routing/data/kl-roadgraph.v1.bin (ARG3 since
+ *     Phase 08.1 — the storage NAME stays v1; the header version is the
+ *     format truth).
  *
  * Constant-mirror law: this script's OPTIMALITY_EPSILON_PCT is asserted EQUAL
  * to the record's epsilon block BEFORE any measurement — a record edit alone
@@ -88,7 +89,7 @@ function toArrayBuffer(buf) {
  *   "unsnapped"  — a record-routed pair whose snap now misses (a D03B class
  *                  break — the pair no longer routes at all).
  *
- * @param graph  decoded RoadGraph (the current ARG2 build)
+ * @param graph  decoded RoadGraph (the current ARG3 build)
  * @param record parsed alt-baseline.json (the frozen pre-ALT record)
  * @param opts   { snap, astar } — the live modules (injected like the corpus core)
  * @returns {{ checks: { D03A: check, D03B: check }, rows: Array, reSnapped: number, pass: boolean }}
@@ -270,7 +271,7 @@ function main() {
   const graph = decodeGraph(toArrayBuffer(readFileSync(GRAPH_PATH)));
   if (graph === null) {
     fail(
-      `${GRAPH_PATH} does not decode (fail-honest null — still ARG1 or corrupt) — rebuild the ARG2 binary: node routing/scripts/build-road-graph.mjs`,
+      `${GRAPH_PATH} does not decode (fail-honest null — the current binary must be ARG3) — rebuild it: node routing/scripts/build-road-graph.mjs`,
     );
   }