Calendar swiping feature disabled

Changes

• Calendar swiping feature needs some serious refactoring due to change of API and bugs. It has been disabled as of this version until further notice.

• Add more styling entry points via CSS Custom Properties so that users can customize the appearance of the date picker such as adding support for dark theme:

  @media (prefers-color-scheme: dark) {
    app-datepicker,
    app-datepicker-dialog {
      --app-datepicker-bg-color: #000;
      --app-datepicker-color: #f5f5f5;
      --app-datepicker-disabled-day-color: rgba(255, 255, 255, .35);
      --app-datepicker-focused-day-color: #000;
      --app-datepicker-selector-color: rgba(255, 255, 255, .55);
      --app-datepicker-separator-color: #000;
      --app-datepicker-weekday-color: rgba(255, 255, 255, .55);
    }
  }