Drop the global _APP_NOTIFICATIONS_WEBHOOK_SECRET env var. There's no
analogous global webhook secret in Appwrite; the existing Webhooks
worker carries a per-webhook signatureKey on the webhook document.
Move the same pattern into the Notification event: each webhook
recipient may carry an optional signatureKey, which the worker
forwards to the Webhook adapter for HMAC-SHA256 signing. Recipients
without a key are delivered unsigned and a tag is logged for audit.
Covers the dedup short-circuit, per-channel dispatch routing, alert
persistence, error tagging, and legacy single-recipient fallback in the
Notifications worker, plus the Console adapter's permission shape and the
Webhook adapter's HMAC-SHA256 signing contract, header layout, response
handling, and unsigned-when-secret-missing behaviour.
Worker dispatch helpers move from private to protected so a test spy can
override them without monkey-patching. The Swoole runtime hook flag
mutation is now guarded by class_exists so the action can run under bare
PHPUnit (no Swoole extension on the test host).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Jake Barnby