refactor: modularize App (001-component-refactor)

[remarkablemark]

What is the motivation for this pull request?

• Modularize App into components
• Remove keyboard shortcuts (conflicts with navigation/accessibility)
• Fix UI bugs and improve copy and add button icons

Checklist:

• Conventional Commits
• Tests
• Documentation

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (99fa4af) to head (af787d6).
⚠️ Report is 26 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##            master        #3   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            9        15    +6     
  Lines          205       180   -25     
  Branches        75        55   -20     
=========================================
- Hits           205       180   -25     

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