security: bump clerk-backend-api and cryptography

[christniel39-glitch]

Summary

Follow-up security dependency update to clear the cryptography CVE path discovered during audit.

Changes

• Upgraded clerk-backend-api:
  • 4.2.0 -> 5.0.2
• Upgraded cryptography:
  • 45.0.7 -> 46.0.5
• Refreshed lockfile:
  • backend/uv.lock

Why this pairing

clerk-backend-api==4.2.0 constrained cryptography to <46.0.0, which blocked applying the patch release. Moving to Clerk 5.x relaxes the bound, allowing cryptography==46.0.5.

Validation

• uv lock resolves successfully with the new versions.
• Backend auth module imports successfully with the upgraded Clerk SDK under runtime env.
• pip-audit against backend direct dependencies reports 0 known vulnerabilities.

[christniel39-glitch]

Companion PR to #274.

Recommended merge order:

1. security: redact gateway tokens + avoid query-string auth leaks #274 first (token/redaction/query-string hardening)
2. security: bump clerk-backend-api and cryptography #275 second (Clerk + cryptography security upgrades)

This keeps rollout cleaner: behavior hardening first, then dependency lift.

[christniel39-glitch]

@abhi1693 heads-up: this companion dependency/security update is also ready for review.

• Scope: clerk-backend-api + cryptography security bump
• Recommended merge order: after security: redact gateway tokens + avoid query-string auth leaks #274

[Copilot]

Pull request overview

This PR updates backend security-related Python dependencies to remove a cryptography CVE path by upgrading clerk-backend-api to a version that no longer constrains cryptography<46.

Changes:

• Bumped clerk-backend-api from 4.2.0 to 5.0.2.
• Bumped cryptography from 45.0.7 to 46.0.5.
• Refreshed backend/uv.lock to reflect the new resolution.

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
backend/pyproject.toml	Updates pinned runtime dependency versions for Clerk SDK and cryptography.
backend/uv.lock	Updates the lockfile entries and resolved artifacts for the upgraded dependencies.