complete favicon support (mostly safari) #306

Favicon from latest Safari (26.1)

Favicon from Safari one version before (18.6)

Bookmark icon from latest Safari (26.1)

Seems like latest version of Safari does support svg favicons but with color: black. It doesn't support dynamic favicon colors. I'm not sure if we can remove the background of svg favicon.

To fully support all types of icons, we need following metadata:

<link rel="icon" href="/favicon.ico" sizes="48x48" />
<link rel="icon" href="/favicon.svg" sizes="any" type="image/svg+xml" />
<link rel="apple-touch-icon" href="/static/apple-touch-icon.png" />

• To support Safari up to 18.6, /favicon.ico here should be actual ico image instead of current svg.
• The apple-touch-icon will allow us to support Safari bookmark icons. It's 180x180 by spec, so we can use dolly logo image here (dolly with eyes).
• The svg icon shouldn't be dynamic. Usually static white svg icon should be fine.