👔(app-impress) add is_public switch button

Add a switch button to the create pad form to
allow the user to set the pad as public or private.

src/frontend/apps/impress/cunningham.ts

@@ -361,6 +361,7 @@ const config = {
         'forms-switch': {
           'handle-border-radius': '2px',
           'rail-border-radius': '4px',
+          'accent-color': 'var(--c--theme--colors--primary-text)',
         },
         'forms-textarea': {
           'border-radius': '0',