Update UI with eye-friendly colour scheme

Replace bright white backgrounds with warmer off-white tones to reduce
eye strain while maintaining good contrast and professional appearance.

Changes:
- Update CSS variables with warmer neutral palette (#f5f3f0 page bg,
  #faf9f7 surfaces, #f0ede8 muted sections)
- Soften primary blue from #2563eb to #3b6fd4
- Update navbar, cards, tables to use new surface colours
- Update upload area, file lists, and icon backgrounds
- Update flag item backgrounds with softer tints
- Update shared components (VeracityScoreCard, FlagsList)

The new colour scheme uses warm off-white/cream tones that are easier
on the eyes than pure white while maintaining professionalism.

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

src/TrueCV.Web/Components/Shared/FlagsList.razor

@@ -61,8 +61,8 @@
 
 <style>
     .flags-list {
-        background-color: #fff;
-        border: 1px solid #dee2e6;
+        background-color: var(--truecv-bg-surface);
+        border: 1px solid var(--truecv-gray-200);
         border-radius: 0.5rem;
         padding: 1.5rem;
     }
@@ -90,17 +90,17 @@
     }
 
     .flag-item.critical {
-        background-color: #f8d7da;
+        background-color: #fdf2f2;
         border-left-color: #dc3545;
     }
 
     .flag-item.warning {
-        background-color: #fff3cd;
+        background-color: #fdfbf0;
         border-left-color: #ffc107;
     }
 
     .flag-item.info {
-        background-color: #cff4fc;
+        background-color: #f0f5fa;
         border-left-color: #0dcaf0;
     }
 

src/TrueCV.Web/Components/Shared/VeracityScoreCard.razor

@@ -32,8 +32,8 @@
         flex-direction: column;
         align-items: center;
         padding: 1.5rem;
-        background-color: #fff;
-        border: 1px solid #dee2e6;
+        background-color: var(--truecv-bg-surface);
+        border: 1px solid var(--truecv-gray-200);
         border-radius: 0.5rem;
     }
 
@@ -52,7 +52,7 @@
 
     .score-background {
         fill: none;
-        stroke: #e9ecef;
+        stroke: var(--truecv-gray-200);
         stroke-width: 3;
     }