docs: link hf CLI Skill from model release checklist (#2508)

Add a tip at the top of the model release checklist pointing to the hf
CLI Skill install guide, so users releasing with a coding agent can have
it handle the upload, model card, and metadata.

Author: gary149

docs/hub/model-release-checklist.md

@@ -3,6 +3,9 @@
 The [Hugging Face Hub](https://huggingface.co/models) is the go-to platform for sharing machine learning models.
 A well-executed release can boost your model's visibility and impact. This section covers **essential** steps for a concise, informative, and user-friendly model release.
 
+> [!TIP]
+> Releasing with a coding agent? Install the [`hf` CLI Skill](./agents-cli) to let your agent handle the upload, model card, and metadata for you.
+
 ## ⏳ Preparing Your Model for Release
 
 ### Upload Model Weights