Emit rebalance clipping diagnostics

crates/fidc-core/tests/explicit_order_flow.rs

@@ -754,6 +754,15 @@ fn rebalance_optimizer_prioritizes_higher_target_weight_when_cash_is_tight() {
             .iter()
             .any(|event| event.symbol == "000002.SZ" && event.side == fidc_core::OrderSide::Buy)
     );
+    assert!(
+        report
+            .diagnostics
+            .iter()
+            .any(|line| line.contains("rebalance_safety_scaled")
+                || line.contains("rebalance_buy_reduced")),
+        "expected rebalance diagnostics when cash is tight, got {:?}",
+        report.diagnostics
+    );
 }
 
 #[test]