Update favicon.ico to include more sizes and use PNG instead of BMP

[andrewlukoshko]

Current favicon.ico contains only 3 sizes and uses BMP format:

% identify favicon.ico 
favicon.ico[0] ICO 48x48 48x48+0+0 8-bit sRGB 0.000u 0:00.000
favicon.ico[1] ICO 32x32 32x32+0+0 8-bit sRGB 0.000u 0:00.000
favicon.ico[2] ICO 16x16 16x16+0+0 8-bit sRGB 15086B 0.000u 0:00.000

I propose to add more sizes and to cover all possible Windows scale factors and usage cases:

% identify favicon.ico 
favicon.ico[0] PNG 144x144 144x144+0+0 8-bit sRGB 8590B 0.000u 0:00.002
favicon.ico[1] PNG 16x16 16x16+0+0 8-bit sRGB 689B 0.000u 0:00.002
favicon.ico[2] PNG 20x20 20x20+0+0 8-bit sRGB 928B 0.000u 0:00.002
favicon.ico[3] PNG 24x24 24x24+0+0 8-bit sRGB 1145B 0.000u 0:00.001
favicon.ico[4] PNG 256x256 256x256+0+0 8-bit sRGB 15874B 0.000u 0:00.001
favicon.ico[5] PNG 30x30 30x30+0+0 8-bit sRGB 1473B 0.000u 0:00.001
favicon.ico[6] PNG 32x32 32x32+0+0 8-bit sRGB 1621B 0.000u 0:00.001
favicon.ico[7] PNG 36x36 36x36+0+0 8-bit sRGB 1866B 0.000u 0:00.001
favicon.ico[8] PNG 40x40 40x40+0+0 8-bit sRGB 2064B 0.000u 0:00.001
favicon.ico[9] PNG 48x48 48x48+0+0 8-bit sRGB 2572B 0.000u 0:00.001
favicon.ico[10] PNG 60x60 60x60+0+0 8-bit sRGB 3275B 0.000u 0:00.001
favicon.ico[11] PNG 64x64 64x64+0+0 8-bit sRGB 3586B 0.000u 0:00.001
favicon.ico[12] PNG 72x72 72x72+0+0 8-bit sRGB 3984B 0.000u 0:00.001
favicon.ico[13] PNG 80x80 80x80+0+0 8-bit sRGB 4522B 0.000u 0:00.001
favicon.ico[14] PNG 96x96 96x96+0+0 8-bit sRGB 57975B 0.000u 0:00.001

We use http://almalinux.org/fav/favicon.ico URL in AlmaLinux OS 8/9 profiles for Windows Terminal in our WSL images so this makes us look pixel perfect for every resolution/scale. Also switched from BMP to PNG to maintain compact size. ICO format with PNG images is supported everywhere nowadays.

[bennyvasquez]

I didn't even realize this was a thing .ico's could do. Looks good to me!

[jonathanspw]

I didn't even realize this was a thing .ico's could do. Looks good to me!

Nor did I. LGTM.

[bennyvasquez]

@andrewlukoshko did you still want to work on this, or shall we close it for now and pick it up again later?