Make header & footer more minimal

@s-small this is a conversation we've been having in other channels that I wanted to move here.

I talked to Lucas about this a bit, and he's about as unopinionated as I am between "make it match citrusbyte.com" and "make it its own thing." The reason I am leaning toward "make it its own thing" is because we do plan and hope to have many other minimal little pages built for other projects we build. If we go with "make it match citrusbyte.com," then all of these pages could easily become out-of-date with citrusbyte.com, when it changes in the future. He also sees no reason to think that we would even keep a header or footer at all, in future versions of citrusbyte.com, and so extracting them to shared components that can be used across our apps doesn't even make sense.

I wanted to run this by you, and see if 1. you agree and if so, 2. wanna design up a minimal header & footer for `thicket-intro`? I was thinking the header could be _just_ the Citrusbyte logo on the left, and the footer could be just the Citrusbyte logo and maybe the social links. But it's up to you, really, as you feel the strongest about this.