WIP: Add decision logging infrastructure

- Add decision_logs table to database schema
- Create decision logger module with comprehensive logging
- Prepare for decision tracking and audit trail

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/logging/__init__.py

@@ -0,0 +1,5 @@
+"""Decision logging and audit trail for trade decisions."""
+
+from src.logging.decision_logger import DecisionLog, DecisionLogger
+
+__all__ = ["DecisionLog", "DecisionLogger"]