Show example GIFs on all examples

**Is your feature request related to a problem? Please describe.**
I'd love to be able to quickly see what the various examples look like in a terminal. Today, some examples have VHS GIFs in their README and others do not.

**Describe the solution you'd like**
Have VHS GIFs in all examples

Inspect the examples and their README files, starting by comparing which examples already include VHS GIFs. Inventory the missing examples and add the corresponding terminal previews so every example README shows a VHS GIF; done means all examples have one.

Written by the indexing model from the issue text.