Motia.dev tutorial in docs (#514)

Co-authored-by: Maria Ines Parnisari <maria.ines.parnisari@authzed.com>
Co-authored-by: Tanner Stirrat <tstirrat@gmail.com>

Author: 3 people

app/spicedb/tutorials/_meta.ts

@@ -1,5 +1,7 @@
 export default {
-  "ai-agent-authorization": "Tutorial: Authorization for AI Agents using SpiceDB",
-  "secure-rag-pipelines": "Tutorial: Securing RAG Pipelines with SpiceDB",
+  "rag-motia-spicedb":
+    "Build a Multi-Tenant RAG with Fine-Grained Authorization using Motia and SpiceDB",
+  "ai-agent-authorization": "Authorization for AI Agents using SpiceDB",
+  "secure-rag-pipelines": "Securing RAG Pipelines with SpiceDB",
   "agentic-rag": "Tutorial: Building Agentic RAG with SpiceDB, LangChain & Weaviate",
 };