Add pipeline tag and license

This PR adds the missing `pipeline_tag` and `license` to the model card metadata. This improves discoverability and clarity for users.

README.md

@@ -1,5 +1,7 @@
 ---
 library_name: transformers
+pipeline_tag: text-generation
+license: apache-2.0
 ---
 
 # STILL-3-TOOL-32B