UI: modernized color palette and improved visual design
- Updated brand palette: modern indigo-violet (#4F46E5) replacing vivid indigo-blue
- Refined neutrals: darker ink (#0F172A), warmer muted tones, cleaner line colors
- Improved semantic colors: emerald ok (#10B981), standard red bad (#EF4444)
- Sidebar: deeper indigo with better contrast
- Glass effects: increased opacity for more refined frosted look
- Background gradient: cleaner, more subtle with new accent colors
- Topbar: uses glass token for consistency
- Service panel: glass-strong backdrop with proper shadow
- FRD/Meeting styles: use CSS variables instead of hardcoded fallbacks
- Progress bars: updated track color to match new muted tone
- Removed duplicate ::selection rule
- Build and tests pass