feat: pass structured output format through to ollama

backend/open_webui/utils/payload.py

@@ -154,6 +154,9 @@ def convert_payload_openai_to_ollama(openai_payload: dict) -> dict:
     )
     ollama_payload["stream"] = openai_payload.get("stream", False)
 
+    if "format" in openai_payload:
+        ollama_payload["format"] = openai_payload["format"]
+
     # If there are advanced parameters in the payload, format them in Ollama's options field
     ollama_options = {}