Update starter kit

[ethanpalm]

This PR updates the starter kit to provide a more guided path through set up with progressive disclosure and a clearer sequence to follow.

Goal is to make it more clear how to deploy and what to do next.

• Streamlined quickstart flow
  • Make it three steps so it's approachable
  • Give a specific change to do to demo updating and publishing changes
• Reorganized content into progressive groups: Getting Started → Customization → Writing Content
• Fixed CLI command inconsistencies
  • Standardized all CLI commands to use mint (not mintlify) across all pages
• Make value props more clear
• Add setup steps for popular AI tools (Cursor, Claude Code, Windsurf)

[Sooooo7]

@ D

[Sooooo7]

#94