docs(librechat): add Ollama local embeddings tip to notes

json/librechat.json

@@ -43,6 +43,10 @@
         {
             "text": "RAG API is included and running on port 8000. Set RAG_OPENAI_API_KEY in /opt/rag-api/.env to enable document Q&A.",
             "type": "info"
+        },
+        {
+            "text": "For local embeddings without an API key, set EMBEDDINGS_PROVIDER=ollama and OLLAMA_BASE_URL=http://<ollama-host>:11434 in /opt/rag-api/.env and restart rag-api.",
+            "type": "info"
         }
     ]
 }