fix: requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-15263096

Author: snyk-bot

requirements.txt

@@ -1,7 +1,7 @@
 anyio>=4.9.0
 cachetools>=6.0.0
 contextvars>=2.4.0
-cryptography==45.0.5
+cryptography==46.0.5
 fastapi[standard]>=0.115.12
 PyJWT>=2.10.1
 starlette >= 0.46.0