Remove old UI sound images

[ffont]

Our local data mount and the CDN still have the sound images of the old UI. We should delete them as they're no longer necessary.

Tentative steps:

• Rename BW image files to adopt the "old" image file path
• Make all image URLs to point to the "old" image file path (which now has the new images)
• Remove the concept of "BW" images from the API responses
• Add a redirect so if someone is still using hardcoded links to BW images URL, it still gets the corresponding images at the new URL