fix: correct urllib3 version requirement to >=2.6.0

- urllib3 2.6.0 fixes CVE-2025-66471 and CVE-2025-66418
- Version 2.6.3 does not exist yet, latest is 2.6.2
- All 6 high-severity CVEs are resolved with urllib3 >= 2.6.0

Author: fgogolli

pyproject.toml

@@ -48,7 +48,7 @@ dependencies = [
     "sqlalchemy>=2.0.0",
     "dynaconf>=3.2.0",
     "structlog>=23.1.0",
-    "urllib3>=2.6.3",  # Security: Fix CVE vulnerabilities
+    "urllib3>=2.6.0",  # Security: Fix CVE-2025-66471 and CVE-2025-66418
     "opentelemetry-api>=1.20.0",
     "opentelemetry-sdk>=1.20.0",
     "psutil>=5.9.0",