Evangelize "rnx-init" command

[afoxman]

Tell the community about using rnx-init to get started with the tools we are building.

• [ ] Video demonstrating "rnx-init" how-to guide for new project and existing project
• [ ] Video should come with a transcript (accessibility) and be translated into other languages (localization), so that we reach as many people as possible.
• [ ] Short blog post explaining how easy it is to get started with rnx-kit, and what you get vs. what it costs. Include link to video and how-to guide.
• [ ] Amplify on Twitter, Discord, and in react-native newsletters.