Complete React migration improvements and fixes

- Fix button styling inconsistency for 'did' button using proper CSS reset
- Replace Font Awesome spinners with yellow color (#fff700) for consistency
- Implement holographic card effects for special status cards (yui, first, etc.)
- Add cached user data loading from /json/users.json for faster initial load
- Fix loading states to show spinners instead of "User not found" messages
- Clean up debug console logs for production readiness
- Add proper error handling for API calls
- Update CSS imports to use local files from /pkg/ directory

🤖 Generated with [Claude Code](https://claude.ai/code)

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

public/pkg/font-awesome/scss/_sizing.scss

@@ -0,0 +1,16 @@
+// sizing icons
+// -------------------------
+
+// literal magnification scale
+@for $i from 1 through 10 {
+  .#{$fa-css-prefix}-#{$i}x {
+    font-size: $i * 1em;
+  }
+}
+
+// step-based scale (with alignment)
+@each $size, $value in $fa-sizes {
+  .#{$fa-css-prefix}-#{$size} {
+     @include fa-size($value);
+  }
+}