Fix: Add MySQL 5.6 compatibility and detailed error logging

Added better error handling and MySQL 5.6 support for Windows Server:

1. Enhanced error logging in app.py:
   - Detailed database error messages with error codes
   - Full stack traces logged to console/PM2
   - Error details returned in JSON for debugging

2. Created app-pymysql.py:
   - Alternative version using PyMySQL instead of mysql-connector-python
   - Better compatibility with older MySQL 5.6 servers
   - Handles bit field conversion from bytes to boolean
   - Pure Python implementation (no C extensions)

3. Added requirements-mysql56.txt:
   - PyMySQL 1.1.0 for MySQL 5.6 compatibility
   - Use this on Windows servers with old MySQL

For production Windows servers with MySQL 5.6, use:
  pip install -r requirements-mysql56.txt
  python app-pymysql.py

For debugging 500 errors, check console/PM2 logs for detailed error messages.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

requirements-frozen.txt

@@ -0,0 +1,9 @@
+blinker==1.9.0
+click==8.3.0
+Flask==3.0.0
+itsdangerous==2.2.0
+Jinja2==3.1.6
+MarkupSafe==3.0.3
+mysql-connector-python==8.2.0
+protobuf==4.21.12
+Werkzeug==3.1.3