Remove next-view-transitions and use native View Transition API

- Remove external next-view-transitions dependency
- Use Next.js 16 native navigation and Safari 18+ native View Transition API
- Add ViewTransitionProvider for minimal wrapping with Safari 18+ detection
- Updated all Link imports from external package to next/link
- Removed link-wrapper.tsx and view-transitions-wrapper.tsx

This resolves Safari compatibility issues while maintaining transitions on modern browsers.

components/theme-toggle.tsx

@@ -22,14 +22,14 @@ export function ThemeToggle() {
   return (
     <button
       type="button"
-      className="inline-flex h-9 w-9 items-center justify-center rounded-full text-accent-textLight transition duration-180 ease-snappy hover:-translate-y-0.5 hover:bg-accent-soft hover:text-accent active:scale-95 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40 dark:text-accent-textDark dark:hover:bg-slate-800 dark:hover:text-accent"
+      className="inline-flex h-9 w-9 items-center justify-center rounded-full text-accent-textLight transition-all duration-300 ease-out-quarter hover:-translate-y-1 hover:scale-110 hover:bg-accent-soft hover:text-accent focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40 dark:text-accent-textDark dark:hover:bg-accent-soft dark:hover:text-accent"
       onClick={() => setTheme(next)}
       aria-label={theme === 'dark' ? '切換為淺色主題' : '切換為深色主題'}
     >
       {isDark ? (
-        <FiSun className="h-4 w-4 rotate-0 text-amber-400 transition-transform duration-260 ease-snappy" />
+        <FiSun className="h-4 w-4 rotate-0 text-amber-400 transition-all duration-500 ease-out-expo" />
       ) : (
-        <FiMoon className="h-4 w-4 rotate-180 text-blue-500 transition-transform duration-260 ease-snappy" />
+        <FiMoon className="h-4 w-4 rotate-180 text-blue-500 transition-all duration-500 ease-out-expo" />
       )}
     </button>
   );