fix(items_table): fix design

[igorsimb]

For #59

Summary by CodeRabbit

• New Features

  • Added multiple options for adding new items with varying button styles.
  • Introduced new styles for table cells, a custom material icon, focus ring adjustments, and toggle buttons in the app's design.

• Style Updates

  • Updated navigation layout for authenticated users, enhancing the positioning of elements.
  • Adjusted padding of the main container by removing specific classes.
  • Enhanced button styling across forms by adding rounded-pill class for a more modern look.
  • Updated table headers for clarity and adjusted styling of the percentage difference column.