Major performance upgrade

[ryanmcd118]

This PR wraps up a major performance pass for lexiQL based on Lighthouse audits. The build is stable, layout is intact, and we’ve cut total asset size by ~70% without losing quality. Webpack builds are leaner, images and videos are optimized, and load times are noticeably faster.

Highlights

• Webpack & JS: Code splitting, tree shaking, modern browser targets, and lazy loading for heavy components.
• Assets: All PNGs converted to WebP (94% smaller), GIFs converted to WebM/MP4 (33% smaller), explicit image dimensions added to reduce layout shift.
• Preloading & Preconnect: LCP image preloaded; preconnects for Google Fonts and external resources.
• Result: ~8MB saved across assets, ~6s faster load on slower connections, improved Core Web Vitals.

Verification

• npm run dev → app loads correctly, optimized assets and fallbacks working.
• npm run build → optimized assets included in production output.
• Tested in modern browsers with fallbacks for older ones.

[ryanmcd118]

👍 Verified & ready to merge.