feat: Major updates to backend structure and security enhancements

- Removed `COMMON_ERRORS.md` file to streamline documentation.
- Added `Flask-Limiter` for rate limiting and `redis` for session management in `requirements.txt`.
- Expanded `ROADMAP.md` to include completed security features and planned enhancements for version 2.2.
- Enhanced `setup_myp.sh` for ultra-secure kiosk installation, including system hardening and security configurations.
- Updated `app.py` to integrate CSRF protection and improved logging setup.
- Refactored user model to include username and active status for better user management.
- Improved job scheduler with uptime tracking and task management features.
- Updated various templates for a more cohesive user interface and experience.

backend/app/static/icons/mercedes-logo.svg

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 192 192" width="192" height="192">
+  <circle cx="96" cy="96" r="96" fill="#000000"/>
+  <path d="M96 12c46.392 0 84 37.608 84 84s-37.608 84-84 84-84-37.608-84-84 37.608-84 84-84m0-12C42.98 0 0 42.98 0 96s42.98 96 96 96 96-42.98 96-96S149.02 0 96 0z" fill="#ffffff"/>
+  <path d="M96 30l21.65 57.68L174 96l-56.35 8.32L96 162l-21.65-57.68L18 96l56.35-8.32L96 30z" fill="#ffffff"/>
+</svg>