feat(n8n): add get-logs action

skills/n8n-webhook/references/payloads.md

@@ -74,6 +74,28 @@ Current sink:
 - key: `actionLog`
 - retained entries: `200`
 
+### `get_logs`
+
+Request:
+
+```json
+{
+  "action": "get_logs",
+  "args": {
+    "limit": 10
+  }
+}
+```
+
+Purpose:
+- return the most recent retained log records from workflow static data
+
+Behavior:
+- default limit: `20`
+- min limit: `1`
+- max limit: `50`
+- entries are returned newest-first
+
 Success shape:
 
 ```json
@@ -81,13 +103,12 @@ Success shape:
   "ok": true,
   "request_id": "optional-uuid",
   "result": {
-    "action": "append_log",
-    "status": "logged",
-    "sink": {
-      "type": "workflow-static-data",
-      "key": "actionLog",
-      "retained_entries": 200
-    }
+    "action": "get_logs",
+    "status": "ok",
+    "count": 2,
+    "total_retained": 7,
+    "retained_entries": 200,
+    "entries": []
   }
 }
 ```
@@ -140,5 +161,5 @@ Success shape:
 
 - Use lowercase kebab-case for webhook paths.
 - Use lowercase snake_case or kebab-case consistently for action names; prefer snake_case for JSON actions if using switch/router logic.
-- Keep names explicit: `openclaw-ping`, `openclaw-action`, `append_log`, `notify`.
+- Keep names explicit: `openclaw-ping`, `openclaw-action`, `append_log`, `get_logs`, `notify`.
 - Avoid generic names like `run`, `task`, or `webhook1`.