docs: add favicon

[rakleed]

No description provided.

[typicode]

Thank you. I've published a new version, could you please add the change to config.mts instead (feel free to open a new PR) and use inline image, like this:

	head: [
		['link', { rel: 'icon', href: 'data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><text y=".9em" font-size="85">🐶</text></svg>' }],
	],