fix(infra): remove --initial-capital from train-best step

train_baseline_rl doesn't accept --initial-capital (only hyperopt and
evaluate binaries do). Removing it fixes the exit code 2 in DQN
hyperopt v3 train-best step.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

infra/k8s/argo/compile-and-train-template.yaml

@@ -478,8 +478,7 @@ spec:
               --trades-data-dir {{workflow.parameters.trades-data-dir}} \
               --output-dir /workspace/output \
               --max-steps-per-epoch {{workflow.parameters.train-epochs}} \
-              $HYPEROPT_FLAG \
-              --initial-capital {{workflow.parameters.initial-capital}}
+              $HYPEROPT_FLAG
 
             echo "=== Training complete ==="
         resources: