polish: smooth site-name scale animation on photography page transition

[kiennt23]

Summary

Closes #337

Fixes the slight snap when the site-name scales from 32px → 50px (via transform: scale(1.5625)) on home → photography navigation.

Root Cause

The FLIP animation completes and calls onComplete, which used a 50ms setTimeout before adding the wide-layout class. This was a race condition — sometimes the browser batched the site-name visibility restore and the scale change into a single paint frame, skipping the CSS transition entirely.

Fix

Replaced setTimeout(() => ..., 50) with double requestAnimationFrame — this guarantees the browser paints the site-name at scale(1) before wide-layout adds scale(1.5625), ensuring the CSS transform 0.4s ease transition always fires.

// Before (race condition)
setTimeout(() => document.body.classList.add("wide-layout"), 50);

// After (guaranteed paint cycle)
requestAnimationFrame(() => requestAnimationFrame(() => {
  document.body.classList.add("wide-layout");
}));

The reverse direction (photography → home) was already smooth — the 400ms delay matches the FLIP duration, so no change needed there.