Unify button, badge, and icon styles across app

[olsonjp]

Problem

• 3+ different "primary button" treatments across screens
• Quick Actions: styled as filled rectangles on Dashboard, outlined chips in Storage
• Sidebar icons, stat-card icons, and Quick Action icons appear from 2+ different families (stroke weights, corner radii don't match)

Solution

• Pick one icon family (Lucide, Phosphor, or Tabler) and apply everywhere
• Standardize button styles (one primary, one secondary)

Priority

P2