ROS 2 docs RAG index and tooling

index/meta.json

@@ -0,0 +1,8 @@
+{
+  "embedding_model": "sentence-transformers/all-MiniLM-L6-v2",
+  "dimensions": 384,
+  "chunks": 5134,
+  "documents": 341,
+  "index": "IndexFlatIP (cosine over normalised vectors)",
+  "source": "repository: https://github.com/ros2/ros2_documentation.git\nref: rolling\ncommit: a74c8f1\nfiles: 342\n"
+}