Summary by cubic

Replaced deprecated asStringOrNull helpers with Zod-based query validation in SSO getServerSideProps. Removed the helpers file to improve type safety and simplify param handling.

• Refactors
  • Added a Zod schema to parse and validate provider, email, and username from query.
  • Deleted apps/web/lib/asStringOrNull.tsx and migrated usage in the SSO route.
  • Switched prisma to a named import and used req consistently with orgDomainConfig.

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