Refa: treat MinerU as an OCR model (#11849)

### What problem does this PR solve?

 Treat MinerU as an OCR model.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)
- [x] Refactoring

conf/llm_factories.json

@@ -5489,6 +5489,14 @@
                     "model_type": "reranker"
                 }
             ]
+        },
+        {
+            "name": "MinerU",
+            "logo": "",
+            "tags": "OCR",
+            "status": "1",
+            "rank": "900",
+            "llm": []
         }
     ]
 }