CVE-2026-28464: OpenClaw has non-constant-time token comparison in hooks authentication

OpenClaw hooks previously compared the provided hook token using a regular string comparison. Because this comparison is not constant-time, an attacker with network access to the hooks endpoint could potentially use timing measurements across many requests to gradually infer the token.

In practice, this typically requires hooks to be exposed to an untrusted network and a large number of requests; real-world latency and jitter can make reliable measurement difficult.