feat(n8n-webhook): add calendar list update delete approval flows

skills/n8n-webhook/references/payloads.md

@@ -250,6 +250,80 @@ Sink:
 - key: `approvalQueue`
 - retained entries: `200`
 
+### `list_upcoming_events`
+
+Request:
+
+```json
+{
+  "action": "list_upcoming_events",
+  "args": {
+    "calendar": "primary",
+    "days": 7,
+    "max": 10,
+    "query": "zap"
+  }
+}
+```
+
+Purpose:
+- queue a host-side upcoming calendar event listing request for approval/audit
+- defaults to the next `7` days when no explicit `from`/`to` window is provided
+
+Approval policy:
+- required: `true`
+- mutation level: `low` (read-only)
+
+### `update_calendar_event`
+
+Request:
+
+```json
+{
+  "action": "update_calendar_event",
+  "args": {
+    "calendar": "primary",
+    "event_id": "example-calendar-event-id",
+    "title": "Updated call with vendor",
+    "start": "2026-03-13T18:15:00Z",
+    "end": "2026-03-13T18:45:00Z",
+    "location": "Updated room",
+    "description": "Updated by OpenClaw action bus.",
+    "send_updates": "none"
+  }
+}
+```
+
+Purpose:
+- queue an update to an existing calendar event behind explicit approval
+- requires `event_id` and at least one patch field (`title`, `start`, `end`, `location`, `description`, or `attendees`)
+
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
+### `delete_calendar_event`
+
+Request:
+
+```json
+{
+  "action": "delete_calendar_event",
+  "args": {
+    "calendar": "primary",
+    "event_id": "example-calendar-event-id",
+    "send_updates": "none"
+  }
+}
+```
+
+Purpose:
+- queue deletion of an existing calendar event behind explicit approval
+
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
 ### `approval_queue_add`
 
 Request: