Setup views: primary-target column, floor-target prune, liveness cutoff

Three follow-ups to the gate probability floor (8f41143):

- Signals table shows the starred primary target (shared primaryTarget
  helper) instead of an independently computed max-probability best,
  so Overview, Signals and ticker details agree by construction.
- Targets pinned at the 3% probability clamp floor collapse to the
  nearest one (enhance_trade_setup + backtest candidates in parity):
  floor-pinned levels are indistinguishable to the model, so farther
  ones were duplicate 3% rows inviting lottery headlines.
- get_trade_setups only returns setups re-emitted within
  LIVE_SETUP_MAX_AGE_DAYS (3): an older latest row means the daily
  scan no longer confirms the setup, and such rows otherwise surface
  forever on Overview/Signals/ticker/alerts. History endpoints keep
  full history.

Backtest on the Jul-3 snapshot is metric-identical to the gate-floor
run on all qualified stats (1089 qualified, Sharpe 2.02, CAGR +49.6%,
DD -15.8%): the prune only removes noise the gate already rejected.

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

app/services/backtest_service.py

@@ -65,6 +65,7 @@ from app.services.qualification import (
 from app.services.recommendation_service import (
     _choose_recommended_action,
     _classify_by_probability,
+    _prune_floor_pinned_targets,
     _risk_level_from_conflicts,
     _select_primary_target,
     _zone_representative_levels,
@@ -179,6 +180,9 @@ def _window_setups(
                 t, dim_scores, None, direction, config
             )
             t["classification"] = _classify_by_probability(t["probability"])
+        # Collapse duplicate floor-pinned lottery targets (parity with
+        # enhance_trade_setup).
+        targets = _prune_floor_pinned_targets(targets)
         primary = _select_primary_target(targets)
         if primary is None:
             continue