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/svgs/solid/face-grin-wide.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><!--! Font Awesome Free 6.5.2 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2024 Fonticons, Inc. --><path d="M256 512A256 256 0 1 0 256 0a256 256 0 1 0 0 512zM388.1 312.8c12.3-3.8 24.3 6.9 19.3 18.7C382.4 390.6 324.2 432 256.3 432s-126.2-41.4-151.1-100.5c-5-11.8 7-22.5 19.3-18.7c39.7 12.2 84.5 19 131.8 19s92.1-6.8 131.8-19zM208 192c0 35.3-14.3 64-32 64s-32-28.7-32-64s14.3-64 32-64s32 28.7 32 64zm128 64c-17.7 0-32-28.7-32-64s14.3-64 32-64s32 28.7 32 64s-14.3 64-32 64z"/></svg>