refactor: improve path resolution safety and configuration robustness

[RinZ27]

Strengthening the project's robustness by addressing identified path resolution and configuration vulnerabilities. These changes focus on practical security improvements and architectural stability.

Key Modifications:

• Path Handling: Switched to using path.basename in file utilities to eliminate potential path traversal risks when looking up file IDs.
• Configuration Security: Implemented a protective guard in the ConfigManager to block illegal property overrides (e.g., __proto__), preventing prototype pollution during configuration updates.
• Container Hardening: Updated the Dockerfile to switch from root to a dedicated vane user, adhering to the principle of least privilege for production deployments.

Everything has been verified against the current codebase structure. No existing functionality is impacted by these surgical safety enhancements.

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Summary by cubic

Strengthens path handling, config updates, and container runtime to reduce traversal and prototype pollution risks and run without root. No functional changes; safer defaults only.

• Refactors
  • Use path.basename when resolving uploaded file IDs to prevent path traversal.
  • Harden ConfigManager by rejecting __proto__, constructor, and prototype keys at any depth to stop prototype pollution.
  • Run the Docker image as non-root user vane; set ownership for /home/vane and /usr/local/searxng and set USER vane.

^{Written for commit ea6dc03. Summary will update on new commits.}

Review in cubic

[cubic-dev-ai]

1 issue found across 3 files

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