feat(n8n-webhook): add gmail draft list/delete/send approval flows

skills/n8n-webhook/references/payloads.md

@@ -150,11 +150,76 @@ Purpose:
 - queue an email draft proposal for approval
 - does **not** send mail directly in the shipped starter workflow
 
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
 Sink:
 - type: `workflow-static-data`
 - key: `approvalQueue`
 - retained entries: `200`
 
+### `list_email_drafts`
+
+Request:
+
+```json
+{
+  "action": "list_email_drafts",
+  "args": {
+    "max": 20,
+    "all": false
+  }
+}
+```
+
+Purpose:
+- queue a host-side Gmail draft listing request for approval/audit
+
+Approval policy:
+- required: `true`
+- mutation level: `low` (read-only)
+
+### `delete_email_draft`
+
+Request:
+
+```json
+{
+  "action": "delete_email_draft",
+  "args": {
+    "draft_id": "r-example-draft-id"
+  }
+}
+```
+
+Purpose:
+- queue deletion of a Gmail draft behind explicit approval
+
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
+### `send_gmail_draft` (alias: `send_approved_email`)
+
+Request:
+
+```json
+{
+  "action": "send_gmail_draft",
+  "args": {
+    "draft_id": "r-example-draft-id"
+  }
+}
+```
+
+Purpose:
+- queue sending of an existing Gmail draft behind explicit approval
+
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
 ### `create_calendar_event`
 
 Request:
@@ -176,6 +241,10 @@ Purpose:
 - queue a calendar event proposal for approval
 - does **not** write to a calendar provider directly in the shipped starter workflow
 
+Approval policy:
+- required: `true`
+- mutation level: `high`
+
 Sink:
 - type: `workflow-static-data`
 - key: `approvalQueue`