Add pipeline tag, license, and paper link

This PR adds the missing `pipeline_tag` and license information to the model card. It also adds a link to the paper on Hugging Face.

README.md

@@ -1,5 +1,7 @@
 ---
-library_name: UniDepth
+library_name: unidepth
+pipeline_tag: depth-estimation
+license: cc-by-nc-4.0
 tags:
 - model_hub_mixin
 - monocular-metric-depth-estimation
@@ -8,4 +10,6 @@ tags:
 
 This model has been pushed to the Hub using the [PytorchModelHubMixin](https://huggingface.co/docs/huggingface_hub/package_reference/mixins#huggingface_hub.PyTorchModelHubMixin) integration:
 - Library: https://github.com/lpiccinelli-eth/UniDepth
-- Docs: [More Information Needed]
+- Docs: [More Information Needed]
+
+This model is presented in the paper [UniDepthV2: Universal Monocular Metric Depth Estimation Made Simpler](https://hf.co/papers/2502.20110).