Implement A5 fundamentals cutover activation

docs/dolt-integration-plan.md

@@ -427,8 +427,9 @@ workstream B — Alpaca remains the price source throughout.
   fundamental-score/ranking changes, require explicit approval. Definition
   changes (e.g. TTM vs provider convention) called out, not averaged away.
   **Status 2026-07-24: the gate has been exercised and the evidence supports
-  approval** — see the handoff section below. What remains of A5 is the
-  activation itself: implementing step (c) and flipping it on.
+  approval** — see the handoff section below. Step (c) is implemented behind the
+  default-off `fundamental_data_sec_dolt_cutover_enabled` SystemSetting; the
+  remaining production action is flipping that switch on and observing it.
 - A6. Remove FMP/Finnhub/Alpha Vantage; keep monitoring + manual fallback.
 
 **Workstream B (independent, start when wanted):**
@@ -491,16 +492,18 @@ Post-fix: candidate scores 504 of 511 vs legacy's 507 (gap = PSKY/Q new registra
 FITB, all explained); revenue-growth agreement 0.0038 median abs delta where both exist.
 Dennis reviewed the evidence 2026-07-24 and directed proceeding to cutover.
 
-**Task 1 — A5 activation (implement step (c) above, ~line 207).** The post-activation
-local refresh of `fundamental_data` does not exist yet. Per the spec: `pe_ratio` and
+**Task 1 — A5 activation (IMPLEMENTED 2026-07-24; production switch remains).** The
+post-activation local refresh of `fundamental_data` derives `pe_ratio` and
 `market_cap` from newest valid snapshots × latest PostgreSQL close, `revenue_growth`
 from snapshots, `earnings_surprise`/`next_earnings_date` from `earnings_events`; mark
 affected cached fundamental scores stale; must run identically when SEC is unreachable.
-Implementation notes from the parity work: consume `fundamentals_derivation.derive()`
-outputs, NOT raw snapshot fields — that path carries the split guard (`ttm_diluted_eps`
+It consumes `fundamentals_derivation.derive()` outputs, NOT raw snapshot fields —
+that path carries the split guard (`ttm_diluted_eps`
 nulls when contaminated, with `ttm_diluted_eps_caveat`) and the multi-class share
-fallback (`shares_outstanding` + `shares_outstanding_estimated`). Activation should be
-an explicit switch (SystemSetting, like `sec_cik_overrides`), default off.
+fallback (`shares_outstanding` + `shares_outstanding_estimated`). Parity and activation
+share the same candidate builder. Activation is the explicit
+`fundamental_data_sec_dolt_cutover_enabled` SystemSetting and defaults off; see
+`docs/fundamentals-deployment.md` for the production flip and rollback procedure.
 
 **Task 2 — A6 decommissioning.** After a short observation window: remove
 FMP/Finnhub/Alpha Vantage providers, config and env keys; keep monitoring + manual