malkhut(wire): venue passed through matrix recording for cross-exchange comparison

- evaluator: passes scenario.venue to matrix.record(venue=...)
- PerformanceMatrix.record(): accepts venue parameter (default='bingx')
- Enables cross-exchange learnings: same strategy tested on BingX vs Binance
  gets separate performance entries per venue

Adversary ecology analysis:
Counterparties operate at ActionKind level (CROSS_SPREAD/PLACE/CANCEL),
not at order-type level. The CWM infers order type from ActionKind:
  CROSS_SPREAD → fills aggressively → equivalent to MARKET
  PLACE → passive quote → equivalent to LIMIT
This is correct and venue-independent. Fee calculation already uses
VenueRules (per-exchange fees). No adversary changes needed.

MALKHUT/malkhut/training/selector.py

@@ -188,8 +188,9 @@ class PerformanceMatrix:
         pnl_bps: float = 0.0,
         drawdown_bps: float = 0.0,
         adverse_fill_ratio: float = 0.0,
+        venue: str = "bingx",
     ) -> None:
-        """Record a strategy's performance in a regime."""
+        """Record a strategy's performance in a regime (optionally venue-tagged)."""
         key = (regime, strategy_id)
         existing = self._scores.get(key)