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/_stacked.scss

@@ -0,0 +1,32 @@
+// stacking icons
+// -------------------------
+
+.#{$fa-css-prefix}-stack {
+  display: inline-block;
+  height: 2em;
+  line-height: 2em;
+  position: relative;
+  vertical-align: $fa-stack-vertical-align;
+  width: $fa-stack-width;
+}
+
+.#{$fa-css-prefix}-stack-1x,
+.#{$fa-css-prefix}-stack-2x {
+  left: 0;
+  position: absolute;
+  text-align: center;
+  width: 100%;
+  z-index: var(--#{$fa-css-prefix}-stack-z-index, #{$fa-stack-z-index});
+}
+
+.#{$fa-css-prefix}-stack-1x {
+  line-height: inherit;
+}
+
+.#{$fa-css-prefix}-stack-2x {
+  font-size: 2em;
+}
+
+.#{$fa-css-prefix}-inverse {
+  color: var(--#{$fa-css-prefix}-inverse, #{$fa-inverse});
+}