feat(health): the gate reads the named report — reads refuse loudly, never rebuild; open serves before it returns; the ceremony door

The read gate stops consulting the unnamed isReady() boolean: every provider
may expose healthReport() (sync, O(1), composed from exact ledgers —
HealthReport with a monotonic generation, per-invariant source
ledger|deep|unledgered, missing {count, sample}), and one readiness
authority (assessProviderHealth) derives the verdict. Unledgered families
are UNKNOWN — never healthy, never broken; a report that throws is a loud
not-ready, never a shrug. Reads at the four index choke points refuse with
the typed NotReady errors, narrated once per (provider, generation) — a
read NEVER starts a store walk:

- the first-read lazy build retires (open builds instead, regardless of
  size — the ≥10k deferral and the "lazy loading on first query" branch go;
  disableAutoRebuild is re-meant honestly in its docs);
- the verify*Live read-path rebuild triggers retire (refuse-or-serve);
- the read-time consistency probe that could launch a dark rebuild from an
  ordinary find() retires;
- repairIndex({ rebuild: ['metadata'|'graph'|'vector'] | 'all' }) is the
  one explicit door: rebuilds the named leg unconditionally and reports
  rebuilt per family; bare repairIndex() stays report-driven.

test(lifecycle): the biography lane — a store's whole life, refereed

tests/lifecycle/: an independent shadow model referees every read after
every chapter (founding, a working day, clean restart, crash, repair,
second life). Chapters 1-3 green. Chapters 4-6 assert the true contract and
are marked .fails as a release-blocking finding (the kill-matrix
convention): after a crash + adopt reopen the metadata index computes its
'catchup' watermark verdict and nothing consumes it — find() serves the
pre-crash index while canonical and counts recover. The catchup wiring is
the cure; a passing .fails will force the marker's removal. The lane runs
in the integration gate (config + coverage guard).

src/types/brainy.types.ts

@@ -1816,10 +1816,16 @@ export interface BrainyConfig {
     | StorageAdapter
 
   /**
-   * Disable the automatic index rebuild check during `init()`. By default
-   * Brainy auto-decides from dataset size: small datasets rebuild missing
-   * indexes inline, large datasets rebuild lazily on first query. Set `true`
-   * only when an operator wants full manual control via `repairIndex()`.
+   * RE-MEANT (the health-gate contract): `init()` (open) always verifies the
+   * durable generation of every derived index, and a needed rebuild ALWAYS
+   * runs at open — it is never deferred to the first read, regardless of
+   * dataset size or this flag. There is no first-query lazy-build path
+   * anymore: a read that finds a provider not serving throws a typed
+   * `*NotReadyError` rather than building anything (see
+   * `assessProviderHealth` / the read gate in `brainy.ts`). Setting this
+   * `true` no longer defers index construction to the first query — it has
+   * no effect on WHEN a needed rebuild runs. Full manual control over
+   * rebuilds remains available via `repairIndex({ rebuild: [...] })`.
    */
   disableAutoRebuild?: boolean