Update Hugging Face Space short description

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

README.md

@@ -5,7 +5,7 @@ colorFrom: red
 colorTo: blue
 sdk: static
 pinned: false
-short_description: Write your description here
+short_description: Recognize persons by face and greet them by name
 tags:
  - reachy_mini
  - reachy_mini_python_app