[landing] Introduce animated eye illustration

Summary: Introduce animated eye illustration exported from After Effects and added @lottiefiles/lottie-player (https://github.com/LottieFiles/lottie-player) to display it. Currently the animation autoplays, will be interactive once @lottiefiles/lottie-interactivity is introduced.

Test Plan: Looks right on Safari/Chrome/Firefox

Reviewers: ashoat

Reviewed By: ashoat

Subscribers: KatPo, palys-swm, Adrian

Differential Revision: https://phabricator.ashoat.com/D1037