Move lobster integration to optional plugin tool

extensions/lobster/README.md

@@ -0,0 +1,38 @@
+# Lobster (plugin)
+
+Adds the `lobster` agent tool as an **optional** plugin tool.
+
+## What this is
+
+- Lobster is a standalone workflow shell (typed JSON-first pipelines + approvals/resume).
+- This plugin integrates Lobster with Clawdbot *without core changes*.
+
+## Enable
+
+Because this tool can trigger side effects (via workflows), it is registered with `optional: true`.
+
+Enable it in an agent allowlist:
+
+```json
+{
+  "agents": {
+    "list": [
+      {
+        "id": "main",
+        "tools": {
+          "allow": [
+            "lobster" // plugin id (enables all tools from this plugin)
+          ]
+        }
+      }
+    ]
+  }
+}
+```
+
+## Security
+
+- Runs the `lobster` executable as a local subprocess.
+- Does not manage OAuth/tokens.
+- Uses timeouts, stdout caps, and strict JSON envelope parsing.
+- Prefer an absolute `lobsterPath` in production to avoid PATH hijack.