Improve model card with metadata and code link

This PR improves the model card by adding the `pipeline_tag` and `library_name` metadata, and includes a link to the Github repository. The `pipeline_tag` is set to `text-classification` as the data filter aids in the text classification domain.

README.md

@@ -1,6 +1,9 @@
 ---
 license: mit
+library_name: fasttext
+pipeline_tag: text-classification
 ---
-This is the fastText pretraining data filter targeting
-the LAMBADA DE task, discussed in the main text of the Perplexity
-Correlations paper: https://arxiv.org/abs/2409.05816
+
+This is the fastText pretraining data filter targeting the LAMBADA DE task, discussed in the main text of the Perplexity Correlations paper: https://arxiv.org/abs/2409.05816
+
+Code: https://github.com/TristanThrush/perplexity-correlations