Add T14 (NPE bug) to TASK_QUEUE.json

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: donald-pinckney

TASK_QUEUE.json

@@ -57,6 +57,15 @@
       "status": "todo",
       "notes": "Do after plugin registration tests exist so we can verify the refactor doesn't break registration. Also resolves T10 (unnecessary MCP reflection)."
     },
+    {
+      "id": "T14",
+      "title": "Fix NPE when ChatResponse metadata is null",
+      "description": "ActivityChatModel.toResponse() passes null metadata to ChatResponse.builder().metadata(null), which causes an NPE in Spring AI's builder. Fix: skip .metadata() call when metadata is null, or pass an empty ChatResponseMetadata.",
+      "severity": "high",
+      "category": "bugfix",
+      "depends_on": [],
+      "status": "todo"
+    },
     {
       "id": "T7",
       "title": "Add max iteration limit to ActivityChatModel tool loop",