migrate landing page (including navbar and footer) components to `@dzcode/ui`

[ZibanPirate]

migrating landing page (including navbar and footer) components to @dzcode/ui

• [x] Base
  • [x] Grid
• [x] Navbar
  • [x] Link button
  • [x] Dropdown
  • [x] Switch
  • [x] Image
  • [x] Text Button Group
• [x] Landing Section
  • [x] Intro Title
  • [x] Intro Subtitle
  • [x] Action Button
  • [x] Link Button
  • [x] Image
• [x] Mobile Section
  • [x] Section Title
  • [x] Section Subtitle
  • [x] Interactive Image
• [x] Roadmap Section
  • [x] Milestones
• [x] Footer
  • [x] Column Title
  • [x] Link Button
• [x] Use React Context on Link component (provide react-router and inject lang code as url prefix) and write useLink hook.
• [x] Remove dead code from components folder
• [x] useColor hook with Color interface.
• [x] Make sure theming is respected in all three components
• [x] Use the new theme component as default and remove the old one.