docs: add generated plugin reference pages

docs/plugins/reference/llm-task.md

@@ -0,0 +1,19 @@
+---
+summary: "Generic JSON-only LLM tool for structured tasks callable from workflows."
+read_when:
+  - You are installing, configuring, or auditing the llm-task plugin
+title: "LLM Task plugin"
+---
+
+# LLM Task plugin
+
+Generic JSON-only LLM tool for structured tasks callable from workflows.
+
+## Distribution
+
+- Package: `@openclaw/llm-task`
+- Install route: included in OpenClaw
+
+## Surface
+
+contracts: tools