add arxiv links

app.py

@@ -70,6 +70,8 @@ with gr.Blocks() as demo:
     This demo accompanies the paper **“Learning to Refocus with Video Diffusion Models”** by Tedla *et al.*, SIGGRAPH Asia 2025. 
     - 🌐 **Project page:** <https://learn2refocus.github.io/> 
     - 💻 **Code:** <https://github.com/tedlasai/learn2refocus/>
+    - 📄 **Paper:** SIGGRAPH Asia 2025 <https://arxiv.org/abs/2512.19823>
+
     
      Upload an image and **specify the input focal position** (these values correspond to iPhone API positions, but approximately linear in diopters (inverse meters): 0 - 5cm, 8 - Infinity).
      Then, click "Generate stack" to generate a focal stack. """