Add pipeline tag to model card

This PR improves the model card by adding the `pipeline_tag: text-to-image` to the metadata. This will enable better discoverability of the model on the Hugging Face Hub, allowing users to filter models by this pipeline tag.

README.md

@@ -1,5 +1,6 @@
 ---
 license: mit
+pipeline_tag: text-to-image
 ---
 
 # Semantics Lead the Way: Harmonizing Semantic and Texture Modeling with Asynchronous Latent Diffusion
@@ -75,4 +76,4 @@ Explicitly **leading semantics ahead of textures with a moderate offset (Δt = 0
   journal={arXiv preprint arXiv:2512.04926},
   year={2025}
 }
-
+```