Generate a cryptographic fingerprint of auth-sensitive headers using SHA-256. Async, but the result is always a stable hex string usable as a cache key segment. Returns "" when no auth headers are present (shared/anonymous cache).
Generate a cryptographic fingerprint of auth-sensitive headers using SHA-256. Async, but the result is always a stable hex string usable as a cache key segment. Returns "" when no auth headers are present (shared/anonymous cache).