Add YAML metadata to model card

- Add license, language, tags for better discoverability
- Include model type, pipeline tag, and base models
- Fix Hugging Face metadata warning

README.md

@@ -1,3 +1,31 @@
+---
+license: mit
+language:
+- ko
+tags:
+- image-classification
+- computer-vision
+- korean
+- secondhand-market
+- e-commerce
+- ensemble
+- tensorflow
+- keras
+datasets:
+- custom
+metrics:
+- accuracy
+model_type: ensemble
+pipeline_tag: image-classification
+widget:
+- src: https://example.com/sample_image.jpg
+  example_title: "Sample Product Image"
+base_model:
+- google/efficientnet-b0
+- microsoft/resnet-50
+- facebook/deit-base-distilled-patch16-224
+library_name: tensorflow
+---
 # Korean Secondhand Market Classifier
 
 ## Model Overview