Add pipeline tag, license, and link to paper

This PR improves the model card for OlmoEarth-v1_2-Small by:
- Adding the `pipeline_tag: image-feature-extraction` and `license: other` metadata.
- Correcting the version typo in the description (from v1.1 to v1.2).
- Linking the model card to the Hugging Face paper page (https://huggingface.co/papers/2605.20804).

README.md

@@ -1,4 +1,9 @@
-OlmoEarth-v1_1-Small is a ViT-Small (36M parameters) foundation model for remote sensing tasks over Sentinel-1, Sentinel-2, and Landsat images or image time series.
+---
+license: other
+pipeline_tag: image-feature-extraction
+---
+
+OlmoEarth-v1_2-Small is a ViT-Small (36M parameters) foundation model for remote sensing tasks over Sentinel-1, Sentinel-2, and Landsat images or image time series, presented in [OlmoEarth v1.2: A more efficient family of OlmoEarth models](https://huggingface.co/papers/2605.20804).
 
 Please see our GitHub and paper for more information about OlmoEarth.