audit: cycle metric-vocabulary tidy — ledger records the retired #147 deferral

Cycle-close audit (architect: drift_found, design core clean). What holds,
architect-confirmed: C18 bit-identity for RunMetrics (prose derived
byte-identically, rng order preserved, registry suite unchanged); the C10
wall (monomorphic R-gates, r_based in the R vocabulary, cross-vocabulary
refusal tested both ways — no leak); C28 direction (trait in aura-analysis,
vocabulary supplied from the outer rungs, zero Cargo edge changes); C1
determinism pinned through the generic path.

Drift items, all resolved as fixes in this commit:
- design ledger: the C28 #147 disposition now records item 2 SHIPPED (the
  A1 cut) with A2 still deliberately deferred; the #136 one-implementor
  clause carries a supersession note (the IC is the second implementor).
- seven stale doc comments describing the pre-#147 or mid-cycle state
  (analysis trait + estimator docs, registry check_r_metric C9 claim,
  engine re-export note, campaign PER_MEMBER_METRICS roster note,
  member-seam guard comment, research vocabulary note) updated to the
  shipped state.
- R_BASED_METRICS is now oracle-pinned against RunMetricKey::r_based()
  in the vocabulary test (it feeds the NonRMetric refusal prose; a
  divergence would have misreported the R-gate silently).

Noted, not amended (history stays): commit 6744f67's body says 'three
syntax-only edits' where the test module actually took five.

No regression scripts are configured (the bench is report-only); the
architect review is the gate. Verification: extended vocabulary test,
campaign suites, analysis/research suites green; clippy --workspace
-D warnings clean.

refs #147

crates/aura-analysis/src/lib.rs

@@ -236,9 +236,9 @@ pub fn permute<T>(xs: &mut [T], rng: &mut SplitMix64) {
 
 /// Per-metric vocabulary a report payload supplies to the registry's
 /// ranking/deflation machinery (#147). Narrow by design (#136): exactly the
-/// surface the backtest metrics (the sole implementor so far) and the
-/// measurement IC (deflatable today via its own permutation-null path, not
-/// yet through this trait) are expected to share. The registry owns the
+/// surface the two production implementors — the backtest metrics
+/// (`RunMetrics`, centred moving-block null) and the measurement IC
+/// (within-run permutation null) — demonstrably share. The registry owns the
 /// family fold — best-of-K, p95, Laplace, dispersion floor — the payload
 /// owns what each metric IS: its name, direction, value read, and what one
 /// draw of its null statistic means.
@@ -266,9 +266,8 @@ pub trait MetricVocabulary: Sized {
 
 /// One-sided Laplace-smoothed tail estimate `(ge + 1) / (n + 1)`: the
 /// probability mass at-or-above an observed statistic given that `ge` of `n`
-/// null draws reached it. Intended as the single source of the formula the
-/// registry's R deflation arm and the CLI's IC reduction each compute inline
-/// today; wiring those call sites to this function is deferred follow-up.
+/// null draws reached it. The single source of the formula: the registry's
+/// R deflation arm and the CLI's IC reduction both call it.
 pub fn one_sided_p_laplace(ge: usize, n: usize) -> f64 {
     (ge + 1) as f64 / (n + 1) as f64
 }