create a favicon

[factory-ben]

@droid create a favicon for the site

[github-actions]

👍 Working on this now...

[github-actions]

I've created a branch droid/issue-16 with favicon implementation:

Changes Made

• Created favicon.svg with a zap/lightning bolt icon matching the site's branding
• Created favicon.ico for legacy browser support
• Created favicon-16x16.png and favicon-32x32.png for standard sizes
• Created apple-touch-icon.png (180x180) for iOS home screen bookmarks
• Added favicon references to both index.html and stats.html

The favicon uses a black background with white lightning bolt, matching the site's dark theme.

To create the PR, visit:
https://github.com/factory-ben/feed/compare/main...droid/issue-16?expand=1&title=Add+favicon+for+the+site

(GitHub Actions token doesn't have permission to create PRs automatically)