GHSA-r5h9-vjqc-hq3r: Nextcloud Talk allowlist bypass via actor.name display name spoofing

In affected versions of the optional Nextcloud Talk plugin (installed separately; not bundled with the core OpenClaw install), an untrusted webhook field (actor.name, display name) could be treated as an allowlist identifier. An attacker could change their Nextcloud display name to match an allowlisted user ID and bypass DM or room allowlists.