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>

tests/unit/test_fundamentals_quality_service.py

@@ -6,7 +6,6 @@ from datetime import date, datetime, timezone
 from app.models.data_import_run import DataImportRun
 from app.models.fundamental_snapshot import FundamentalSnapshot
 from app.models.sec_filing_gap import SecFilingGap
-from app.models.settings import SystemSetting
 from app.models.ticker import Ticker
 from app.services import fundamentals_quality_service
 
@@ -19,12 +18,6 @@ async def test_latest_sec_validation_blocks_deferred_and_no_history_ciks(
     healthy = Ticker(symbol="HEALTHY", cik="0000000003")
     db_session.add_all([missing, no_history, healthy])
     await db_session.flush()
-    db_session.add(
-        SystemSetting(
-            key="fundamental_data_sec_dolt_cutover_enabled",
-            value="true",
-        )
-    )
     db_session.add(
         DataImportRun(
             source="sec_facts",
@@ -44,38 +37,11 @@ async def test_latest_sec_validation_blocks_deferred_and_no_history_ciks(
     }
 
 
-async def test_sec_quality_gate_is_inactive_before_cutover(db_session):
-    ticker = Ticker(symbol="SHADOW", cik="0000000042")
-    db_session.add(ticker)
-    await db_session.flush()
-    now = datetime.now(timezone.utc)
-    db_session.add(
-        SecFilingGap(
-            cik=ticker.cik,
-            accession="SHADOW-Q",
-            form="10-Q",
-            index_date=date.today(),
-            reason="not_in_companyfacts",
-            first_seen_at=now,
-            last_attempted_at=now,
-        )
-    )
-    await db_session.flush()
-
-    assert await fundamentals_quality_service.blocked_ticker_ids(db_session) == set()
-
-
-
-
 async def test_active_gap_is_blocked_until_a_later_filing_supersedes_it(db_session):
     ticker = Ticker(symbol="HIST", cik="0000000043")
     now = datetime.now(timezone.utc)
     db_session.add_all([
         ticker,
-        SystemSetting(
-            key="fundamental_data_sec_dolt_cutover_enabled",
-            value="true",
-        ),
         SecFilingGap(
             cik=ticker.cik,
             accession="HIST-Q",
@@ -116,10 +82,6 @@ async def test_gap_without_index_date_uses_first_seen_date_for_supersession(
     first_seen = datetime(2026, 5, 1, 12, tzinfo=timezone.utc)
     db_session.add_all([
         ticker,
-        SystemSetting(
-            key="fundamental_data_sec_dolt_cutover_enabled",
-            value="true",
-        ),
         SecFilingGap(
             cik=ticker.cik,
             accession="DATELESS-Q",
@@ -157,10 +119,6 @@ async def test_ticker_quality_explains_no_xbrl_block(db_session):
     ticker = Ticker(symbol="NEWREG", cik="0000000044")
     db_session.add_all([
         ticker,
-        SystemSetting(
-            key="fundamental_data_sec_dolt_cutover_enabled",
-            value="true",
-        ),
         DataImportRun(
             source="sec_facts",
             status="promoted",