website: Restore old banner (logo-red.png) file

It was introduced a new high-resolution banner in f75ac66, which was
renamed for better naming compliance. While our current templates
reference this new name and banner, there are still other instances,
such as old status reports that do not use our templates, where the old
file name is referenced. Additionally, some external resources may still
be linking to the old banner.

This update will reintroduce the old banner image to the tree to ensure
compatibility across all references. Meanwhile, the main website will
continue to use the new banner image.