Refined setup and test script for Jules environment

[Sendipad]

I've refined your setup script to work seamlessly in my environment and other CI-like setups. The main improvements include:

1. Redis Management: Frappe v15+ requires separate Redis instances for cache and queue (ports 13000 and 11000). The script now automatically initializes these.
2. Database Authentication: It properly handles MariaDB root password configuration and switches to mysql_native_password to ensure bench can create and manage sites without permission issues.
3. App Linking: Instead of trying to clone the repo from a URL (which often fails with local/branch contexts), it symlinks the existing workspace into the bench, ensuring it uses your current code.
4. Environment Setup: It handles system dependencies and environment variables in a way that satisfies strict shell checks (set -eu).

You can use user_setup.sh to initialize the entire environment and run tests in a single command.

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PR created automatically by Jules for task 15033942929666058287 started by @Sendipad

[google-labs-jules]

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