📋 Redesign: List View → Clean Minimal

[krusty-agent]

Redesigns the list view with rounded cards, collapsed Done section, bottom add input, and amber progress bar

Changes

• Rounded cards: Each item is now in its own rounded card with subtle amber border instead of a single card with dividers
• Collapsed Done section: Checked items are hidden under a collapsible 'Done' section with item count badge (collapsed by default)
• Bottom add input: The add item input moved from top to bottom of the list for a cleaner flow
• Amber progress bar: Progress bar now uses warm amber gradient matching the design system (was green)
• Cream/amber accents: Done section uses amber-toned text and badges