Refactor code for improved readability and consistency

- Cleaned up whitespace and formatting in various files including http.py, language.py, logger.py, safe_exec.py, and SQL migration scripts.
- Consolidated import statements and removed unnecessary blank lines.
- Updated logging configuration for better clarity.
- Enhanced the safe execution code with improved error handling and logging.
- Removed commented-out code and unnecessary variables in backfill_zero_trades.py and other scripts.
- Added a pyproject.toml for Ruff and Vulture configuration.
- Introduced requirements-dev.txt for development dependencies.
- Removed commented-out stock entries in init.sql for cleaner migration scripts.

backend_api_python/scripts/run_calibration.py

@@ -7,10 +7,11 @@ Usage:
   AI_CALIBRATION_MARKET=Crypto python scripts/run_calibration.py
   AI_CALIBRATION_MARKETS=Crypto,USStock python scripts/run_calibration.py
 """
-import sys
-import os
 
-sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
+import os
+import sys
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 
 from app.services.ai_calibration import AICalibrationService