Add swipe-to-delete and improve UI design (for Routines, Nutrition Plans Screens)

[Hamed233]

Proposed Changes

• Added swipe-to-delete functionality using Dismissible widget in both Routines and Nutrition Plans.
• Improved UI/UX of routine and plan cards:
  • Rounded corners, shadows, consistent spacing
  • Better typography and color contrast
• Retained delete icon for manual deletion with confirmation dialogs
• Snackbar feedback after successful deletion

[Dieterbe]

Added swipe-to-delete functionality using Dismissible widget in both Routines and Nutrition Plans.

in my android email app (bluemail), i sometimes accidentally delete stuff when i try to swipe up/down but it's not perfectly vertical. so i hope we don't introduce such issues here