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/KanbanColumn.tsx

@@ -40,9 +40,9 @@ export function KanbanColumn({
         style={{ backgroundColor: colorMap[color] }}
       >
         <div className="flex items-center justify-between">
-          <h2 className="font-display text-lg font-bold uppercase flex items-center gap-2 text-[var(--color-neo-text)]">
+          <h2 className="font-display text-lg font-bold uppercase flex items-center gap-2 text-[var(--color-neo-text-on-bright)]">
             {title}
-            <span className="neo-badge bg-white text-[var(--color-neo-text)]">{count}</span>
+            <span className="neo-badge bg-[var(--color-neo-card)] text-[var(--color-neo-text)]">{count}</span>
           </h2>
           {(onAddFeature || onExpandProject) && (
             <div className="flex items-center gap-2">
@@ -58,7 +58,7 @@ export function KanbanColumn({
               {onExpandProject && showExpandButton && (
                 <button
                   onClick={onExpandProject}
-                  className="neo-btn bg-[var(--color-neo-progress)] text-black text-sm py-1.5 px-2"
+                  className="neo-btn bg-[var(--color-neo-progress)] text-[var(--color-neo-text-on-bright)] text-sm py-1.5 px-2"
                   title="Expand project with AI (E)"
                 >
                   <Sparkles size={16} />