chore: decommission FMP, Finnhub and Alpha Vantage (A6)

The A5 cutover has been on and observed in production, so SEC Company Facts +
DoltHub earnings are already the live source for `fundamental_data`. This
removes everything the legacy path still occupied.

Gone: the three providers and their config/env keys; the weekly
`fundamental_collector` job; the cutover toggle (SEC + Dolt is now the
unconditional path, so `off` can no longer silently freeze scoring inputs); the
A5 parity report, whose deltas became structurally zero once the candidate
builder started writing the table it compared against; and the FMP tier of
universe bootstrap.

Two behavioral notes:

- Disabling **SEC Fundamentals Import** now stops the SEC network fetch only.
  The local cache refresh moved outside the job-enable check, because candidates
  also derive from daily closes and earnings events — freezing those on an
  ingestion pause would stale scoring with no fallback left to recover from.
- `/ingestion/fetch?sources=fundamentals` still accepts the key and reports
  `skipped`; there is no per-ticker fetch any more.

Migration 029 does not blanket-delete the leftover settings rows. Migrations run
before the service restart, and pre-A6 code reads an absent `job_*_enabled` row
as *enabled* — so the two behavior-bearing keys become tombstones pinned to safe
values (hidden in Admin) and only the inert three are deleted. Removing the
provider keys from the production `.env` is the matching rollout step.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

scripts/reparse_fundamentals.py

@@ -15,10 +15,10 @@ Cost: a reparse cannot be served from the database -- the facts a fixed parser n
 accepts were never stored -- so it refetches Company Facts for every tracked issuer
 under the SEC fair-access throttle. Expect a long run and a lot of network.
 
-Scope note: this rewrites ``fundamental_snapshots`` only. As of the A5 gate those
-rows feed the fundamentals API/UI and the parity report; scoring still reads the
-legacy ``fundamental_data`` table, so a reparse does not move composite scores or
-backtests until the cutover happens.
+Scope note: this rewrites ``fundamental_snapshots`` only. Those rows now feed both
+the fundamentals API/UI *and* — through the nightly ``fundamental_data`` refresh —
+the fundamental dimension of the composite score, so a reparse does move scores
+and backtests. Run it deliberately.
 
 Examples
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