feat(forward): support webhook subscriptions and signed deliveries

Author: moonyue-w

CHANGELOG.md

@@ -5,6 +5,12 @@ existing `0.1.0` release; earlier development prereleases are not listed.
 
 ## [Unreleased]
 
+### Added
+
+- Add Forward Webhook endpoint creation, listing, retrieval, partial update, deletion, enable/disable and synthetic test delivery.
+- Add raw-body webhook signature verification with HMAC-SHA256, multiple v1 signatures and a 300-second timestamp window; include receiver examples and offline contracts.
+
+
 ## [0.8.0]
 
 ### Fixed

README.md

@@ -764,3 +764,7 @@ Runnable scenarios live in `examples/`, organized by mode, with one file per sce
 ## License
 
 Released under the [MIT License](LICENSE).
+
+## Forward Webhooks (next release)
+
+Manage webhook endpoints and verify signed event deliveries. See [Webhook usage and receiver examples](docs/webhooks.md).