add stream demo

README.md

@@ -105,6 +105,7 @@ tokenizer = AutoTokenizer.from_pretrained('openbmb/MiniCPM-V-4_5', trust_remote_
 image = Image.open('./assets/minicpmo2_6/show_demo.jpg').convert('RGB')
 
 enable_thinking=False # If `enable_thinking=True`, the thinking mode is enabled.
+stream=True # If `stream=True`, the answer is string
 
 # First round chat 
 question = "What is the landform in the picture?"
@@ -113,9 +114,14 @@ msgs = [{'role': 'user', 'content': [image, question]}]
 answer = model.chat(
     msgs=msgs,
     tokenizer=tokenizer,
-    enable_thinking=enable_thinking
+    enable_thinking=enable_thinking,
+    stream=True
 )
-print(answer)
+
+generated_text = ""
+for new_text in answer:
+    generated_text += new_text
+    print(new_text, flush=True, end='')
 
 # Second round chat, pass history context of multi-turn conversation
 msgs.append({"role": "assistant", "content": [answer]})
@@ -123,9 +129,14 @@ msgs.append({"role": "user", "content": ["What should I pay attention to when tr
 
 answer = model.chat(
     msgs=msgs,
-    tokenizer=tokenizer
+    tokenizer=tokenizer,
+    stream=True
 )
-print(answer)
+
+generated_text = ""
+for new_text in answer:
+    generated_text += new_text
+    print(new_text, flush=True, end='')
 ```
 
 You will get the following output: