🔒 [security fix] Run container as non-root user

[max-ostapenko]

🎯 What: Modified the Dockerfile to run the application as the non-root node user instead of root.

⚠️ Risk: Running a container as root increases the risk if the application is compromised. An attacker could potentially gain root access to the container, making it easier to escape the container or access sensitive host resources.

🛡️ Solution:

• Switched to the built-in node user provided by the base image.
• Ensured the /app directory and its contents are owned by the node user.
• Updated the npm cache mount to be accessible by the node user.
• Adhered to the principle of least privilege.

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PR created automatically by Jules for task 17915203525899158463 started by @max-ostapenko

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