Setup UI

[Shuhala]

To do

• Global settings
• Layout
  • Setup theme styles
  • Improve SideMenu
  • Add custom color palette
• Implement CodeMirror
• Routing
  • Confirm which router we want to use
  • Find elegant way to manage paths
  • Set default path on startup
• i18n
• Keyboard shortcuts

Other:

• How to useRef
• document vs. window listeners