Security fixes from Esprit scan

[esprit-security-scan]

Security Fixes

This PR contains automated security fixes generated by Esprit.

Modified Files

• backend/prisma/schema.prisma (modified)
• backend/src/planner/planner.service.ts (modified)

Scan Details

• Scan ID: 52911ddc
• Files changed: 2

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This PR was automatically generated by Esprit

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