add gradio entry file

app.py

@@ -0,0 +1,29 @@
+from transformers import pipeline
+import gradio as gr
+import os
+
+# 1. 建立情緒分析管線
+sent_cls = pipeline(
+    task="sentiment-analysis",
+    model="uer/roberta-base-finetuned-jd-binary-chinese"  # 雙分類
+)
+
+# 2. 推論函式
+def classify(text: str):
+    if not text.strip():
+        return {"error": "請輸入文字"}
+    res = sent_cls(text)[0]
+    return {"label": res["label"], "score": round(res["score"], 4)}
+
+# 3. Gradio 介面
+demo = gr.Interface(
+    fn=classify,
+    inputs=gr.Textbox(lines=4, placeholder="輸入評論…"),
+    outputs="json",
+    title="中文情緒分析 Demo",
+    description="RoBERTa 中文二分類情緒分析（positive/negative）"
+)
+
+if __name__ == "__main__":
+    # localhost:7860 預覽
+    demo.launch(share=True)