fix collection clear

app/rag.py

@@ -107,9 +107,8 @@ class ChatPDF:
         return streaming_response
 
     def clear(self):
-        if self.doc_ids:
-            self.client.delete(collection_name="rag_documents", points_selector=self.doc_ids)
-            self.pdf_count = 0
-            self.text_chunks = []
-            self.doc_ids = []
-            self.nodes = []
+        self.client.delete_collection(collection_name="rag_documents")
+        self.pdf_count = 0
+        self.text_chunks = []
+        self.doc_ids = []
+        self.nodes = []