fix(profile): add the missing demo animation asset

Both READMEs point at a demo animation that was never committed, so the
hero image renders broken for anyone visiting the organization profile.

Claude-Session: https://claude.ai/code/session_01L5wZb1mDtLnrfAXkzSrTFD

README.md

@@ -32,7 +32,7 @@
 
 <p align="center">
   <a href="https://drive.google.com/file/d/1Td7bPj-vSIjByO5UIGwOhZstPwcz0tfm/preview">
-    <img src="profile/assets/Fundusnap_Demo_Video.png" width="640" alt="Watch the Fundusnap demo video"/>
+    <img src="profile/assets/demo.gif" width="100%" alt="Watch the Fundusnap demo video"/>
   </a>
 </p>