fix: Reconfigure backend to use non-Dockerized MySQL

[k-zehnder]

Description

This pull request transitions from Dockerized MySQL to a host-based setup to resolve data access inconsistencies during container restarts. The host-based configuration offers better stability, resource usage, and easier management.

Changes Made

• Replaced Dockerized MySQL with host-based MySQL.
• Updated backend connection settings to support host-side MySQL.

Testing

• Verified backend connection to host-based MySQL.
• Performed CRUD operations to ensure stable data handling.
• Rebooted the server to confirm MySQL autostart and consistent access.

Checklist

• Code follows project guidelines and best practices.
• Thoroughly reviewed and tested the changes.
• Updated or added unit tests to ensure correctness.
• All tests pass with changes.
• No known security vulnerabilities introduced.
• Considered impact on performance, scalability, and maintainability.
• Documentation updated to reflect changes.