feat(ui): comprehensive design system improvements

This PR addresses 53 design issues identified in the UI codebase,
implementing a more consistent and polished neobrutalism design system.

Typography:
- Improved font stacks with proper fallbacks
- Added font smoothing for crisp text rendering

Color/Theme:
- Added neutral scale (50-900) for consistent grays
- Added semantic log level colors with dark mode variants
- Added category colors for feature cards
- Added GLM badge color variable
- Full dark mode support for all new variables

Design Tokens:
- Spacing scale (xs to 2xl)
- Z-index scale (dropdown to toast)
- Border radius tokens
- Inset shadow variants

Animations:
- New transition timing variables
- New easing curves (bounce, smooth, out-back)
- Slide-in animations (top/bottom/left)
- Bounce, shake, scale-pop animations
- Stagger delay utilities
- Enhanced YOLO fire effect with parallax layers

Components:
- Button size variants (sm/lg/icon) and loading state
- Input variants (error/disabled/textarea)
- Badge color and size variants
- Card elevation variants (elevated/flat/sunken)
- Progress bar shimmer animation
- Stronger modal backdrop with blur
- Neobrutalist tooltips
- Enhanced empty state with striped pattern

Component Fixes:
- Replaced hardcoded colors with CSS variables
- Fixed ProgressDashboard percentage alignment
- Improved ChatMessage role-specific styling
- Consistent category badge colors in FeatureModal
- Improved step input styling in forms

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

ui/src/components/ProjectSelector.tsx

@@ -65,7 +65,7 @@ export function ProjectSelector({
       {/* Dropdown Trigger */}
       <button
         onClick={() => setIsOpen(!isOpen)}
-        className="neo-btn bg-white text-[var(--color-neo-text)] min-w-[200px] justify-between"
+        className="neo-btn bg-[var(--color-neo-card)] text-[var(--color-neo-text)] min-w-[200px] justify-between"
         disabled={isLoading}
       >
         {isLoading ? (
@@ -108,7 +108,7 @@ export function ProjectSelector({
                     key={project.name}
                     className={`flex items-center ${
                       project.name === selectedProject
-                        ? 'bg-[var(--color-neo-pending)]'
+                        ? 'bg-[var(--color-neo-pending)] text-[var(--color-neo-text-on-bright)]'
                         : ''
                     }`}
                   >