fix: rename plan skill to generate to avoid name collision with built-in /plan

.claude-plugin/marketplace.json

@@ -10,7 +10,7 @@
       "name": "agent-loop",
       "source": "./",
       "description": "Autonomous generator-evaluator agent loop for long-running coding tasks. Plan interactively, then execute with full visibility.",
-      "version": "0.3.0",
+      "version": "0.4.0",
       "author": {
         "name": "Sheldon"
       },