Add the "Add repository to my Home Assistant" blue button to all
addon README files that were missing it. This makes it easier for
new HA users to add the repository with a single click.
Updated 59 addon READMEs:
- 51 with standard Installation section format
- 8 with non-standard or missing Installation sections
Co-authored-by: alexbelgium <44178713+alexbelgium@users.noreply.github.com>