fix(rag): Auto-create Qdrant collection on first index

Collections may not exist if init_collections() failed at startup
(e.g. Qdrant not ready). Now index_documents() ensures the
collection exists before upserting.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

rag-service/qdrant_client_wrapper.py

@@ -105,6 +105,13 @@ class QdrantClientWrapper:
     # Indexing
     # ------------------------------------------------------------------
 
+    async def ensure_collection(self, name: str, vector_size: int = 1024) -> None:
+        """Create collection if it doesn't exist."""
+        try:
+            self.client.get_collection(name)
+        except Exception:
+            await self.create_collection(name, vector_size)
+
     async def index_documents(
         self,
         collection: str,
@@ -118,6 +125,10 @@ class QdrantClientWrapper:
                 f"vectors ({len(vectors)}) and payloads ({len(payloads)}) must have equal length"
             )
 
+        # Auto-create collection if missing
+        vector_size = len(vectors[0]) if vectors else 1024
+        await self.ensure_collection(collection, vector_size)
+
         if ids is None:
             ids = [str(uuid.uuid4()) for _ in vectors]