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/app/utils/language.py

@@ -9,7 +9,6 @@ from __future__ import annotations
 
 from typing import Optional
 
-
 SUPPORTED_LANGS = {
     "en-US",
     "zh-CN",
@@ -82,5 +81,3 @@ def detect_request_language(flask_request, body: Optional[dict] = None, default:
         return lang
 
     return default
-
-