Refactor: Replace historical information integration method from conc…

[5Hyeons]

Changed the method of integrating historical information features into the diffusion model.
Previously, historical information features were processed through a GNN, then a style was predicted using a style_predictor, and the result was concatenated with h_bert before being fed into the diffusion model.

This has been updated to directly use the historical information features as a context condition in the diffusion model, leveraging cross-attention instead of concatenation.

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기존에는 historical information feature를 GNN을 통해 처리한 후, style_predictor를 사용하여 스타일을 추론하고, 이를 h_bert와 concat하여 diffusion model에 입력하는 방식을 사용했습니다.

이를 변경하여 historical information feature를 diffusion 모델의 context condition으로 직접 사용하고, concat 대신 cross-attention 방식을 활용하도록 수정했습니다.